Autonomous driving system and control method of autonomous driving system

ABSTRACT

An autonomous driving system configured to perform an autonomous driving of a vehicle includes a trigger input request unit configured to perform a trigger input request for requesting a driver of the vehicle to perform a trigger input for causing the vehicle to pass through a target point if the autonomously driving vehicle approaches the target point set in advance and positioned on a traveling route of the vehicle, a trigger input detection unit configured to detect the driver&#39;s trigger input, and a vehicle control unit configured to cause the vehicle to pass through the target point if the trigger input is detected, and causes the vehicle to decelerate and stop without passing through the target point if the trigger input is not detected.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.17/520,004 filed Nov. 5, 2021, which is a continuation of U.S.application Ser. No. 16/397,447 filed Apr. 29, 2019, (now U.S. Pat. No.11,492,000), which claims the benefit of priority from Japanese PatentApplication No. 2018-100893, filed May 25, 2018. The entire disclosuresof the prior applications are considered part of the disclosure of theaccompanying continuation application, and are hereby incorporated byreference.

TECHNICAL FIELD

The present disclosure relates to an autonomous driving system and acontrol method of the autonomous driving system.

BACKGROUND

In the related art, Japanese Unexamined Patent Publication No.2016-24572 is known as a technical literature relating to an autonomousdriving system. This publication discloses that, in a traffic signalrecognition used for the autonomous driving, for a traffic signalexisting in front of a vehicle, the traffic signal is detected from aposition where a vehicle can stop.

SUMMARY

Incidentally, it is not easy to maintain perfect accuracy of trafficsignal recognition or the like in the autonomous driving. Therefore, itis desirable to obtain a driver's decision at an appropriate positioneven during the autonomous driving.

According to an aspect of the present disclosure, there is provided anautonomous driving system configured to perform an autonomous driving ofa vehicle, the system includes a trigger input request unit configuredto perform a trigger input request for requesting a driver of thevehicle to perform a trigger input for causing the vehicle to passthrough a target point if the autonomously driving vehicle approachesthe target point set in advance and positioned on a traveling route ofthe vehicle, a trigger input detection unit configured to detect thedriver's trigger input, and a vehicle control unit configured to causethe vehicle to pass through the target point if the trigger input isdetected, and causes the vehicle to decelerate and stop without passingthrough the target point if the trigger input is not detected.

According to an autonomous driving system of the aspect of the presentdisclosure, if the autonomously driving vehicle approaches the targetpoint such as an intersection, the driver is requested to perform thetrigger input for the vehicle to pass through the target point, and thevehicle is caused to pass through the target point if the trigger inputis detected, and the vehicle is caused to decelerate and stop at thetarget point without passing through the target point if trigger inputis not detected. Therefore, in the autonomous driving system, it ispossible to cause the vehicle to pass through the target point afterobtaining the driver's decision whether or not to pass through thetarget point.

In the autonomous driving system of the aspect of the presentdisclosure, the vehicle control unit may be configured to cause thevehicle to pass through the target point without performing thedeceleration of the vehicle if the trigger input is detected beforestarting the deceleration of the vehicle for causing the vehicle to stopwithout passing through the target point.

In the autonomous driving system of the aspect of the presentdisclosure, the vehicle control unit may be configured to cause thevehicle to stop the deceleration and to pass through the target point ifthe trigger input is detected after starting the deceleration of thevehicle for causing the vehicle to stop without passing through thetarget point.

In the autonomous driving system of the aspect of the presentdisclosure, the system may include a traffic signal recognition unitconfigured to recognize a lighting state of a traffic signal which islocated in the target point and is corresponding to the traveling routeof the vehicle. The trigger input request unit may be configured tonotify the driver that the traffic signal is recognized as not being ina passing permitted state and to perform a trigger input re-request ifthe traffic signal is recognized as not being in the passing permittedstate and the trigger input is detected. The vehicle control unit may beconfigured to cause the vehicle to pass through the target point if thetrigger input is detected after the trigger input re-request, and may beconfigured to cause the autonomously driving vehicle to decelerate andstop without passing through the target point if the trigger input isnot detected after the trigger input re-request.

In the autonomous driving system of the aspect of the presentdisclosure, the trigger input request unit may be configured to notifythe driver that the switching of the traffic signal to a state otherthan the passing permitted state is recognized and to perform thetrigger input re-request if the switching of the traffic signal to thestate other than the passing permitted state is recognized after thetrigger input is detected. The vehicle control unit may be configured tocause the vehicle to pass through the target point if the trigger inputis detected after the trigger input re-request, and may be configured tocause the autonomously driving vehicle to decelerate and stop withoutpassing through the target point if the trigger input is not detectedafter the trigger input re-request.

In the autonomous driving system of the aspect of the presentdisclosure, the trigger input detection unit may be configured to detectat least two inputs as the trigger input among an input by a driver'smanual operation to a trigger input unit provided in the vehicle, aninput by a driver's acceleration operation to an accelerator pedal ofthe vehicle, and an input by a driver's contact to a touch sensor of thevehicle. In the trigger input re-request, the trigger input request unitmay be configured to request the driver to perform an input of which thetype is different from that of the trigger input before the re-request.

According to another aspect of the present disclosure, there is provideda control method of an autonomous driving system that performs anautonomous driving of a vehicle, the method includes: requesting adriver of the vehicle to perform a trigger input for causing the vehicleto pass through a target point if the autonomously driving vehicleapproaches the target point set in advance; detecting the driver'strigger input; and controlling the autonomously driving vehicle to passthrough the target point if the trigger input is detected, and todecelerate and stop without passing through the target point if thetrigger input is not detected.

According to the control method of the autonomous driving system inanother aspect of the present disclosure, if the autonomously drivingvehicle approaches the target point such as an intersection, the driveris requested to perform the trigger input for the vehicle to passthrough the target point, and the vehicle is caused to pass through thetarget point when the trigger input is detected, and the vehicle iscaused to decelerate and stop at the target point without passingthrough the target point when trigger input is not detected. Therefore,in the control method of the autonomous driving system, it is possibleto cause the vehicle to pass through the target point after obtainingthe driver's decision whether or not to pass through the target point.

In the control method of the autonomous driving system in another aspectof the present disclosure, in the step of controlling the vehicle, thevehicle may be caused to pass through the target point withoutperforming a deceleration of the vehicle if the trigger input isdetected before starting the deceleration of the vehicle for causing thevehicle to stop without passing through the target point.

In the control method of the autonomous driving system in another aspectof the present disclosure, in the step of controlling the vehicle, thevehicle may be caused to stop the deceleration and to pass through thetarget point if the trigger input is detected after starting thedeceleration of the vehicle for causing the vehicle to stop withoutpassing through the target point.

The control method of the autonomous driving system in another aspect ofthe present disclosure may further include: recognizing a lighting stateof a traffic signal which is located in the target point and iscorresponding to a traveling route of the vehicle; and firstre-requesting for notifying the driver that the traffic signal isrecognized as not being in a passing permitted state and performing atrigger input re-request if the traffic signal is recognized as notbeing in the passing permitted state and the trigger input is detected.In the step of controlling the vehicle, the vehicle may be caused topass through the target point if the trigger input is detected after thetrigger input re-request, and the autonomously driving vehicle may becaused to decelerate and stop without passing through the target pointif the trigger input is not detected after the trigger input re-request.

The control method of the autonomous driving system in another aspect ofthe present disclosure may further include: second re-requesting fornotifying the driver that the switching of the traffic signal to a stateother than the passing permitted state is recognized and performing thetrigger input re-request if the switching of the traffic signal to thestate other than the passing permitted state is recognized after thetrigger input is detected. In the step of controlling the vehicle, thevehicle may be caused to pass through the target point if the triggerinput is detected after the trigger input re-request, and theautonomously driving vehicle may be caused to decelerate and stopwithout passing through the target point if the trigger input is notdetected after the trigger input re-request.

In the control method of the autonomous driving system in another aspectof the present disclosure, in the step of detecting the trigger input,at least two inputs may be detected as the trigger input, among an inputby a driver's manual operation to a trigger input unit provided in thevehicle, an input by a driver's acceleration operation to an acceleratorpedal of the vehicle, and an input by a driver's contact to a touchsensor of the vehicle. In the step of requesting the trigger input, inthe trigger input re-request, the driver may be requested to perform aninput of which the type is different from that of the trigger inputbefore the re-request.

As described above, according to the autonomous driving system in anaspect of the present disclosure and the control method of theautonomous driving system in another aspect of the present disclosure,it is possible to cause the vehicle to pass through the target pointafter obtaining the driver's decision whether or not to pass through thetarget point.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating an autonomous driving systemaccording to an embodiment.

FIG. 2A is a plan view illustrating a situation in which a vehicleapproaches an intersection where a traffic signal is in a passingpermitted state.

FIG. 2B is a graph illustrating a vehicle speed profile when a triggerinput is detected.

FIG. 3A is a plan view illustrating a situation in which the vehicleapproaches the intersection where the traffic signal is in a passingprohibited state.

FIG. 3B is a graph illustrating a vehicle speed profile when the triggerinput is not detected.

FIG. 4A is a plan view illustrating a situation in which the vehicleapproaches the intersection where the traffic signal is in the passingpermitted state.

FIG. 4B is a graph illustrating a vehicle speed profile when a triggercancellation is detected after the trigger input.

FIG. 5A is a plan view illustrating a situation in which the vehicleapproaches the intersection where the traffic signal is in the passingpermitted state.

FIG. 5B is a graph illustrating a vehicle speed profile if the triggerinput is detected after deceleration of the vehicle starts.

FIG. 6A is a plan view illustrating a situation in which the vehicleapproaches the intersection where the traffic signal is in the passingprohibited state.

FIG. 6B is a graph illustrating the vehicle speed profile when thetrigger input re-request is performed after the trigger input.

FIG. 7A is a plan view illustrating a situation where the vehicleapproaching the intersection where the traffic signal is in the passingpermitted state.

FIG. 7B is a graph illustrating a vehicle speed profile when a triggerinput is detected after the trigger input re-request is performed.

FIG. 8A is a plan view illustrating a situation in which the trafficsignal is switched to a state other than the passing permitted statewhile the vehicle approaches the intersection.

FIG. 8B is a graph illustrating a vehicle speed profile if the triggerinput is detected after the trigger input re-request is performed due toswitching of the traffic signal.

FIG. 9A is a plan view illustrating a situation in which the trafficsignal is switched to the passing permitted state while the vehicleapproaches the intersection.

FIG. 9B is a graph illustrating a vehicle speed profile when a firsttrigger input is detected after a notification of switching the trafficsignal to the passing permitted state after the deceleration of thevehicle starts while the trigger input is not detected.

FIG. 10A is a plan view illustrating a situation in which the vehicleattempts to turn right in the intersection where there is no trafficsignal.

FIG. 10B is a graph illustrating a vehicle speed profile when thetrigger input is detected.

FIG. 11A is a plan view illustrating a situation in which the vehicleattempts to turn right in the intersection where there is no trafficsignal.

FIG. 11B is a graph illustrating the vehicle speed profile when thetrigger input is not detected.

FIG. 12 is a flowchart illustrating stop route generation processing.

FIG. 13 is a flowchart illustrating trigger input detection processingfor a target point where there is a traffic signal.

FIG. 14 is a flowchart illustrating additional processing after thetrigger input.

FIG. 15 is a flowchart illustrating additional processing when thepassing route is executed.

FIG. 16 is a flowchart illustrating additional processing when the stoproute is executed.

FIG. 17 is a flowchart illustrating trigger input detection processingfor the target point where there is no traffic signal.

DETAILED DESCRIPTION

Hereinafter, embodiments of the present disclosure will be describedwith reference to the drawings.

FIG. 1 is a block diagram illustrating an autonomous driving systemaccording to an embodiment. An autonomous driving system 100 illustratedin FIG. 1 is mounted on a vehicle such as a passenger car, and performsan autonomous driving of the vehicle. The autonomous driving system 100starts the autonomous driving of the vehicle when a start operation(such as pressing a start button for starting the autonomous driving,voice input, or the like) for the autonomous driving is performed by theoccupant. The autonomous driving is a vehicle control that causes thevehicle to autonomously travel toward a destination set in advance. Inthe autonomous driving, the driver does not need to perform a drivingoperation, and the vehicle travels autonomously.

When the autonomously driving vehicle approaches a target point such asan intersection, the autonomous driving system 100 requests the driverfor a trigger input to pass through the target point. The autonomousdriving system 100 causes the vehicle to pass through the target pointwhen the trigger input by the driver is detected, and to stop withoutpassing through the target point when the trigger input is not detected.The details of the target point and the trigger input will be describedlater.

Configuration of Autonomous Driving System

As illustrated in FIG. 1 , the autonomous driving system 100 includes anelectronic control unit (ECU) 10 that performs overall management of thesystem. The ECU 10 is an electronic control unit including a centralprocessing unit (CPU), read only memory (ROM), random access memory(RAM), and the like. In the ECU 10, for example, various functions arerealized by loading a program stored in the ROM into the RAM andexecuting the program loaded in the RAM by the CPU. The ECU 10 may beconfigured with a plurality of electronic units.

The ECU 10 is connected to a GPS receiver 1, an external sensor 2, aninternal sensor 3, a map database 4, an accelerator pedal sensor 5, asteering touch sensor 6, a driver monitor camera 7, a human machineinterface (HMI) 8, and an actuator 9.

The GPS receiver 1 measures a position of the vehicle (for example, thelatitude and longitude of the vehicle) by receiving signals from threeor more GPS satellites. The GPS receiver 1 transmits information on themeasured position of the vehicle to the ECU 10.

The external sensor 2 is a detection device that detects a surroundingenvironment of the vehicle. The external sensor 2 includes at least oneof a camera and a radar sensor.

The camera is an imaging device that images an external situation of thevehicle. The camera is provided on the inside of a windshield of thevehicle. The camera transmits the imaging information relating to theexternal situation of the vehicle to the ECU 10. The camera may be amonocular camera or may be a stereo camera.

The radar sensor is a detection device that detects objects around thevehicle using radio waves (for example, millimeter waves) or light. Theradar sensor includes, for example, at least one of the millimeter waveradar or a light detection and ranging (LIDAR). The radar sensortransmits the radio wave or light to the surroundings of the vehicle,and detects the objects by receiving radio waves or light reflected fromthe objects. The radar sensor transmits the detected object informationto the ECU 10. The objects include fixed objects such as guard rails andbuildings, as well as moving objects such as pedestrians, bicycles, andother vehicles. The external sensor 2 does not necessarily need toinclude a radar sensor.

The internal sensor 3 is a detection device that detects a travelingstate of the vehicle. The internal sensor 3 includes a vehicle speedsensor, an accelerator sensor, and a yaw rate sensor. The vehicle speedsensor is a measuring device that measures a speed of the vehicle. Asthe vehicle speed sensor, for example, a vehicle wheel speed sensor isused, which is provided on vehicle wheels of the vehicle or on a driveshaft rotating integrally with vehicle wheels, and measures a rotationalspeed of the vehicle wheels. The vehicle speed sensor transmits themeasured vehicle speed information to the ECU 10.

The accelerator sensor is a measuring device that measures anacceleration of the vehicle. The accelerator sensor includes, forexample, a longitudinal accelerator sensor that measures acceleration inthe longitudinal direction of the vehicle and a lateral acceleratorsensor that measures a lateral acceleration of the vehicle. Theaccelerator sensor, for example, transmits the acceleration informationof the vehicle to the ECU 10. The yaw rate sensor is a measuring devicethat measures a yaw rate (rotation angular velocity) around the verticalaxis at the center of gravity of the vehicle. As the yaw rate sensor,for example, a Gyro sensor can be used. The yaw rate sensor transmitsthe measured yaw rate information of the vehicle to the ECU 10.

The map database 4 is a database that stores map information. The mapdatabase 4 is formed, for example, in a hard disk drive (HDD) mounted onthe vehicle. The map information includes position information on alane, information on a shape of the lane (for example, a curve, a lanewidth, or the like), position information on a stop lone, information onposition of a merge point and a branch, and information on the positionof buildings. The map information also includes speed relatedinformation such as a legal speed associated with the position orsection on the map. The map information includes position information ofmarking objects such as utility poles used for vehicle positionrecognition. The map database 4 may be stored in a server such as amanagement center that can communicate with the vehicle.

Data relating to a target point to be described later may be stored inthe map database 4 in advance. In the map database 4, for example, dataon whether or not a position on the map becomes a candidate for a targetpoint may be stored. The data relating to the target point may be storedin a database different from the map database 4. The data relating tothe target point may not be included in the database in the vehicle, andit may be given from the remote data server by the communicationfunction.

The accelerator pedal sensor 5 is a sensor that detects an operation ofthe accelerator pedal by the driver. The accelerator pedal sensor 5 isprovided on the accelerator pedal of the vehicle and measures an amountof operation of the accelerator pedal performed by the driver. Theaccelerator pedal sensor 5 transmits an accelerator operation signalcorresponding to the amount of operation of the accelerator pedalperformed by the driver to the ECU 10.

The steering touch sensor 6 is provided on a steering wheel and detectsa touch by the driver. For example, a capacitance type touch sensor canbe used as the steering touch sensor 6. The steering touch sensor 6transmits a contact signal to the ECU 10 when the driver touches thesteering wheel. The steering touch sensor 6 may be provided on the leftand right sides of the steering wheel so as to be able to detect thatthe driver touches the steering wheel with both hands. In addition, thesteering touch sensor 6 may be configured to be capable of detecting agripping force with which the driver grips the steering wheel.

The driver monitor camera 7 is an imaging device that images the driverof the vehicle. The driver monitor camera 7 is provided, for example, atthe position of the front of the driver on the cover of the steeringcolumn of the vehicle, and images the driver. A plurality of drivermonitor cameras 7 may be provided in order to image the driver from aplurality of directions. The driver monitor camera 7 transmitsinformation of imaging the driver to the ECU 10.

The HMI 8 is a device that performs inputting and outputting of theinformation between the autonomous driving system 100 and the occupants.The HMI 8 includes, for example, a display, a speaker, and the like. TheHMI 8 performs lighting or blinking of a lamp of an instrument panel,image output on the display and audio output from the speaker accordingto a control signal from the ECU 10. The display may be a head-updisplay.

The HMI 8 includes various input units for receiving the inputs from theoccupants. The HMI 8 may include an autonomous driving start input unitfor starting the autonomous driving of the vehicle and an autonomousdriving end input unit for ending the autonomous driving. The autonomousdriving start input unit and the autonomous driving end input unit maybe a button type or a lever type, and are not particularly limited. Theinput unit may be shared for both the autonomous driving start and theautonomous driving ending. The HMI 8 may have a function of voicerecognition (voice input).

The HMI 8 includes a trigger input unit 8 a for a driver to manuallyperform a trigger input. The trigger input unit 8 a may be a button typeor a lever type, and is not particularly limited as long as it can bemanually operated by the driver. The trigger input unit 8 a is provided,for example, on any of the instrument panel, the steering column, and onthe floor. The trigger input unit 8 a may also serve as another inputunit such as an autonomous driving start input unit.

The HMI 8 includes a trigger cancellation unit 8 b for the driver tomanually perform a trigger cancellation. The trigger cancellation unit 8b may be a button type or a lever type, and is not particularly limitedas long as it can be manually operated by the driver. The trigger inputunit 8 a is provided, for example, on any of the instrument panel, thesteering column, and on the floor. The trigger cancellation unit 8 b mayalso serve as another input unit such as an autonomous driving end inputunit and may also serve as the trigger input unit 8 a. For example, thetrigger cancellation can be input by pulling down the lever-type triggerinput unit 8 a in the direction different from the case of triggerinput. In addition, the trigger cancellation may also be input by longpressing the button-type trigger input unit 8 a for more than a certaintime. Furthermore, the trigger may be input while the driver continuesto operate the trigger input unit 8 a (for example, while continues topress the button-type trigger input unit, or while continues to holddown the lever-type trigger input unit), the trigger may be cancelled byreleasing the trigger input unit 8 a.

The actuator 9 is a device used for controlling the vehicle. Theactuator 9 includes at least a throttle actuator, a brake actuator and asteering actuator. The throttle actuator controls a driving force of thevehicle by controlling an amount of air (throttle opening degree)supplied to the engine according to the control signal from the ECU 10.If the vehicle is a hybrid vehicle, in addition to the amount of airsupplied to the engine, the control signal from the ECU 10 is input to amotor as a power source, and the driving force of the vehicle iscontrolled. If the vehicle is an electric vehicle, instead of thethrottle actuator, the control signal from the ECU 10 is input to amotor as a power source, and the driving force of the vehicle iscontrolled. The motor as the power source in these cases configures theactuator 9.

The brake actuator controls the brake system according to the controlsignal from the ECU 10 and controls a braking force applied to thewheels of the vehicle. For example, a hydraulic brake system can be usedas the brake system. The steering actuator controls the driving of anassist motor controlling a steering torque of an electric power steeringsystem according to the control signal from the ECU 10.

Next, a functional configuration of the ECU 10 will be described. TheECU 10 includes a vehicle position recognition unit 11, an externalenvironment recognition unit 12, a travel state recognition unit 13, aposition determination unit 14, a route generation unit 15, a triggerinput request unit 16, a trigger input detection unit 17, a trafficsignal recognition unit 18, and a vehicle control unit 19. A part of thefunctions of the ECU 10 described above may be performed by a servercapable of communicating with the vehicle.

The vehicle position recognition unit 11 recognizes a position of thevehicle on the map based on the position information from the GPSreceiver 1 and the map information in the map database 4. In addition,the vehicle position recognition unit 11 recognizes position informationof the marking object included in the map information in the mapdatabase 4 and performs the vehicle position recognition with highaccuracy using the result of detection performed by the external sensor2 using the simultaneous localization and mapping (SLAM) technology. Thevehicle position recognition unit 11 may recognize the position of thevehicle on the map using a known method.

The external environment recognition unit 12 recognizes the externalsituation around the vehicle based on the result of detection (theobject information by the radar sensor and/or the imaging information bythe camera) performed by the external sensor 2. The external environmentincludes a situation of objects around the vehicle. The situation of theobject is, for example, a relative position and a relative speed of theobject relative to the vehicle. The external environment may includerecognition results of lane lines (a lane boundary line, a center line,and the like) around the vehicle. The external environment recognitionunit 12 recognizes the relative position of the lane line relative tothe vehicle by well-known white line recognition based on the result ofdetection of the external sensor 2.

The travel state recognition unit 13 recognizes the travel state of thetraveling vehicle based on the result of measurement performed by theinternal sensor 3. The travel state includes the speed of the vehicle,the acceleration of the vehicle, and the yaw rate of the vehicle.Specifically, the travel state recognition unit 13 recognizes the speedof the vehicle based on the vehicle speed information from the vehiclespeed sensor. The travel state recognition unit 13 recognizes theacceleration (a longitudinal acceleration and a lateral acceleration) ofthe vehicle based on the vehicle speed information from the acceleratorsensor. The travel state recognition unit 13 recognizes the direction ofthe vehicle based on the yaw rate information from the yaw rate sensor.

The position determination unit 14 determines a position relationbetween the autonomously driving vehicle and the target point. Theposition determination unit 14 determines the position relation betweenthe autonomously driving vehicle and the target point positioned on thetraveling route for the autonomous driving. The traveling route is theroute on which the vehicle travels in autonomous driving. Details of thetraveling route will be described later.

The target point is a point to which the driver is requested to performthe trigger input before passing through the target point. As anexample, the target point includes an intersection. The intersectionalso includes a circular intersection (roundabout).

The target point may be determined by the relationship between thevehicle and the traveling route of the autonomous driving. The targetpoint may not include the intersection where the vehicle travelsstraight in the autonomous driving but may include the intersectionwhere the vehicle turns right or left in the autonomous driving. Thetarget point may include a merging point where the vehicle merges into amain lane from a merging lane. The target point may not include amerging point with a good visibility, but may include a merging pointwith a poor visibility. The merging point with a poor visibility is amerging point where the detection range of the external sensor 2 for thevehicle traveling in the merging lane is blocked more than a certainrange by, for example, a wall. Similarly, the target point may notinclude the intersection with a good visibility, but may include theintersection with a poor visibility where the detection range of theexternal sensor 2 is blocked more than a certain range by a building orthe like around the intersection.

The target point may include a pedestrian cross-walk. The target pointmay not include the pedestrian cross-walk with good visibility, but mayinclude a pedestrian cross-walk with a poor visibility where thedetection range of the external sensor 2 is blocked more than a certainrange by a wall or the like in the traveling direction of the vehicle.

The target point may be distinguished between a target point withtraffic signal and a target point where there is no traffic signal. Thetarget point where there is a traffic signal means a target point wherethe traffic signal corresponding to the traveling route of the vehicleis installed. Even if the traffic signal is present at the target point,if the traffic signal does not correspond to the traveling route of thevehicle (for example the traffic signal does not face the vehicle on thetraveling route), such a target point is not the target point for thevehicle. The target point may be distinguished between an intersectionwhere there is a traffic signal and an intersection where there is notraffic signal. The target point may not include the intersection wherethere is no traffic signal and may include the intersection where thereis a traffic signal. In addition, the target point may be distinguishedbetween a pedestrian cross-walk where there is a traffic signal and apedestrian cross-walk where there is no traffic signal. A stop line maybe set as the target point.

In addition, the target point may include a point a certain distancebefore from the intersection, the pedestrian cross-walk, the mergingpoint and the like described above. The target point may include a pointwhere the driver performed an operation of finishing the autonomousdriving (such as an override operation) in the past. The target pointmay include an entry point of a section where a lane width is restricteddue to a road construction or the like. In addition, the target pointmay include a point where there is a step or a dent on the road on whichthe driver of the vehicle feels a great shaking. The target point mayinclude an entrance gate of a toll road. The target point may include anentry point of a private land.

The position determination unit 14 determines whether or not thedistance between the autonomously driving vehicle and the target pointis equal to or shorter than a route generation threshold value based onthe position of the vehicle on the map, the map information and thetraveling route for the autonomous driving. The distance between theautonomously driving vehicle and the target point is a distance betweenthe vehicle and the target point on the traveling route for theautonomous driving. The route generation threshold value is a thresholdvalue set in advance used for starting the generation of a stop route (avehicle stop speed profile). The details of the stop route will bedescribed later. The route generation threshold value may be changedaccording to the speed of the vehicle.

The position determination unit 14 determines whether or not theautonomously driving vehicle approaches the target point. For example,when the vehicle reaches a trigger request position set in advance, theposition determination unit 14 determines that the vehicle approachesthe target point. The trigger request position can be a position wherethe distance between the autonomously driving vehicle and the targetpoint is equal to or shorter than a trigger request threshold value. Thetrigger request threshold value is a threshold value set in advance fordetermining the start of the trigger input request that is forrequesting the driver to perform the trigger input. The trigger requestthreshold value may be set as a different value depending on the targetpoint. When the generation of the stop route using the route generationthreshold value is performed, the trigger request threshold value issmaller than the route generation threshold value.

It is not necessary to set the trigger request position, but theposition determination unit 14 may determine that the vehicle approachesthe target point when the distance between the autonomously drivingvehicle and the target point becomes equals to or shorter the triggerrequest threshold value.

In addition, the position determination unit 14 may determine theapproach of the vehicle to the target point using a time to arrivalrather than the distance. The position determination unit 14 maydetermine that the vehicle approaches the target point if the time toarrival in which the vehicle arrives at the target point becomes equalto or shorter than a trigger request time threshold value. The triggerrequest time threshold value is a threshold value corresponding to thetrigger request threshold value described above. The time to arrival canbe calculated from, for example, the distance between the vehicle andthe target point and the vehicle speed profile (or the current vehiclespeed) included in the route for the autonomous driving.

The route generation unit 15 generates a route (trajectory) to be usedfor the autonomous driving of the vehicle. The route generation unit 15generates the route for the autonomous driving based on a destinationset in advance, the map information in the map database 4, the positionof the vehicle recognized by vehicle position recognition unit 11, theexternal environment of vehicle recognized by external environmentrecognition unit 12, and the travel state (the vehicle speed, the yawrate, and the like) recognized by the travel state recognition unit 13.The destination may be set by the occupant of the vehicle or may be theautomatically proposed by the autonomous driving system 100 or by thewell-known navigation system.

The route generation unit 15 obtains the traveling route for theautonomous driving based on the destination, the map information, andthe position of the vehicle on the map. The traveling route is a routeon which the vehicle travels in autonomous driving and is a route fromthe position of the vehicle on the map (the current position) to thedestination. The traveling route may be set by a well-known navigationsystem. The traveling route can be represented as a route on alane-by-lane basis, for example. The route generation unit 15 generatesa route for autonomously driving the vehicle along the traveling routefrom the map information.

The route includes a path on which the vehicle travels in the autonomousdriving and the vehicle speed profile for the autonomous driving. Thepath is a trajectory on which the autonomously driving vehicle willtravel on the traveling route. The path can be data of the steeringangle change (a steering angle profile) of the vehicle corresponding tothe position on the traveling route, for example. The position on thetraveling route is, for example, a set longitudinal position which isset at a predetermined interval (for example, 1 m) in the travelingdirection of the traveling route. The steering angle profile is data inwhich the target steering angle is associated with each set longitudinalposition.

The route generation unit 15 generates the path on which the vehicletravels based on, for example, the traveling route, the map information,the external environment of the vehicle, and the traveling state of thevehicle. The route generation unit 15 generates the path such that thevehicle passes through the center of the lane included in the travelingroute.

Instead of the steering angle profile, a steering torque profile inwhich the target steering torque is associated with each setlongitudinal position may be used. Instead of the steering angleprofile, a lateral position profile in which a target lateral positionis associated with each set longitudinal position may be used. Thetarget lateral position is a target position in the width direction ofthe lane. In this case, the set longitudinal position and the targetlateral position may be collectively set as one position coordinate.

The vehicle speed profile is data in which the target vehicle speed isassociated with each set longitudinal position, for example. The setlongitudinal position may be set based on the travel time of the vehicleinstead of the distance. The set longitudinal position may be set as anarrival position of the vehicle after one second and the arrivalposition of the vehicle after two seconds.

The route generation unit 15 generates the vehicle speed profile basedon speed related information such as a legal speed included in, forexample, the path and the map information. Instead of the legal speed, aset speed may be used, which is set in advance for the position or thesection on the map. The route generation unit 15 generates the route forthe autonomous driving from the path and the vehicle speed profile.

The route generation unit 15 generates a passing route for passingthrough the target point if the target point is included in thetraveling route for the autonomous driving. The route generation unit 15generates the passing route based on, for example, the position of thevehicle on the map, the map information, the external environment of thevehicle, and the traveling state of the vehicle. The passing routeincludes a passing path and a vehicle passing speed profile. The passingpath is a path for causing the vehicle to pass the target point alongthe traveling route. The vehicle passing speed profile is a vehiclespeed profile that causes vehicle to pass the target point at thevehicle speed corresponding to the legal speed or the like at the targetpoint.

If the position determination unit 14 determines that the distancebetween the autonomously driving vehicle and the target point becomesequal to or shorter than the route generation threshold value, the routegeneration unit 15 generates a stop route that causes the vehicle tostop without passing through the target point. The route generation unit15 generates the stop route based on, for example, the position of thevehicle on the map, the map information, the external environment of thevehicle, and the traveling state of the vehicle. The route generationunit 15 generates the stop route according to the target point.

The stop route includes a stop path and a vehicle stop speed profilethat causes the vehicle to decelerate and to stop without passingthrough the target point. The stop path is a path for causing thevehicle to stop without passing through the target point. The stop pathmay be the same as the passing path. The stop path and the passing pathare the same paths, for example, when the autonomously driving vehiclegoes straight through the intersection which is the target point. Thevehicle stop speed profile is, for example, a vehicle speed profile thatcauses the vehicle to gradually decelerate and to stop without passingthrough the target point. In the vehicle stop speed profile, theposition at which the deceleration is started for stopping the vehicleis assumed to be a brake start position.

The stop position of the vehicle on the stop route is not particularlylimited as long as the position is not a position after the targetpoint. The stop position of the vehicle may be a position before thetarget point or may be position within the target point (within theintersection, or the like). The stop position of the vehicle can be, forexample, a position of the stop line before the target point. The stopposition of the vehicle may be set before the target point as much as aset distance on the traveling route. The set distance is a distance setin advance (for example, 1 m).

If the position determination unit 14 determines that the autonomouslydriving vehicle approaches the target point, the trigger input requestunit 16 performs the trigger input request for requesting the driver toperform the trigger input. The trigger input is an input fortransferring a driver's decision of causing the vehicle to pass throughthe target point to the autonomous driving system 100.

The trigger input request unit 16 performs the trigger input request onthe driver by transmitting a control signal to the HMI 8 and outputtinga voice from the speaker of the HMI 8. For example, if the target pointis an intersection where there is a traffic signal, the trigger inputrequest unit 16 performs the trigger input request by causing thespeaker to output a voice saying “Please check the traffic signal andperform the trigger input if passing is permitted”. The trigger inputrequest unit 16 may perform the trigger input request by outputting animage by a display, or may perform the trigger input request by both theimage output and the voice output. Instead of the image output by thedisplay, the lamp or the like of an instrument panel may be turned on ormay be blinked.

In addition, the trigger input request unit 16 performs variousnotifications on the driver according to a result of recognition of thetraffic signal performed by the traffic signal recognition unit 18described later. The trigger input request unit 16 performs the triggerinput re-request according to the result of recognition of the trafficsignal. Details of the various notifications and trigger inputre-request will be described later.

The trigger input detection unit 17 detects the trigger input. If aninput is made by the driver's manual operation of the trigger input unit8 a provided in the vehicle (for example, if the button-type triggerinput unit 8 a is pressed), the trigger input detection unit 17 detectsthe trigger input.

The trigger input detection unit 17 may be capable of detecting pluraltypes of trigger inputs. That is, the trigger input is not limited toone type, and equal to or more than two types of trigger input may beprepared.

The trigger input detection unit 17 may detect the trigger input if aninput is made by the driver's accelerator operation on the acceleratorpedal of the vehicle. In this case, the trigger input detection unit 17detects the trigger input based on the accelerator operation signal fromthe accelerator pedal sensor 5. The trigger input detection unit 17detects the trigger input, for example, when it is detected that anamount of operation (amount of depression) on the accelerator pedal bythe driver is equal to or larger than a certain amount.

The trigger input detection unit 17 may detect the trigger input when aninput is made by the driver's touch on the steering touch sensor 6 ofthe vehicle. In this case, the trigger input detection unit 17 detectsthe trigger input based on the contact signal from the steering touchsensor 6.

The trigger input detection unit 17 may be configured to detect thetrigger input when, for example, it is detected that the driver's bothhands are in contact with the steering wheel after the trigger inputrequest. If the driver's both hands are in contact with the steeringwheel before the trigger input request, the trigger input detection unit17 may detect the trigger input when the driver makes both hands be incontact again with the steering wheel after releasing both hands fromthe steering wheel after the trigger input request. The trigger inputdetection unit 17 may detect the trigger input by touching the steeringwheel with one hand.

The trigger input detection unit 17 may detect the trigger input from acombination of a plurality of inputs. The trigger input detection unit17 may detect the trigger input based on, for example, the acceleratoroperation signal from the accelerator pedal sensor 5, the contact signalfrom the steering touch sensor 6, and the information of imaging thedriver from the driver monitor camera 7. Specifically, the trigger inputdetection unit 17 may detect the trigger input if the driver turnshis/her face toward the front of the vehicle while both hands are incontact with the steering wheel and when the accelerator pedal isoperated to equal to or larger than a certain amount.

The trigger input detection unit 17 may detect the trigger input basedon the information of imaging the driver from the driver monitor camera7 and the voice recognition in the HMI 8. If it is detected that a voicecorresponding to a predetermined trigger input (for example, a voice forrequesting for the vehicle to pass through the target point) is issuedafter the trigger input request while the driver is looking straightahead, the trigger input detection unit 17 may detect the trigger input.

The trigger input detection unit 17 may detect the trigger input basedon the contact signal from the steering touch sensor 6, the informationof imaging the driver from the driver monitor camera 7, and the externalenvironment of the vehicle. Specifically, the trigger input detectionunit 17 may detect the trigger input when it is detected from theinformation of imaging the driver that the driver's line of sight isdirected to the traffic signal in front of the vehicle and when it isdetected that the driver's both hands hold the steering wheel with equalto or stronger than a certain grasping force.

The trigger input detection unit 17 may detect a driver's braking stanceas one of the elements of the combination for detecting the triggerinput. The braking stance is a state in which the driver's foot isplaced on the brake pedal. The braking stance can be detected by thebrake pedal sensor of the vehicle, for example. The trigger inputdetection unit 17 may detect the trigger input when, for example, thedriver is facing the front of the vehicle and both hands are in contactwith the steering wheel, and when the braking stance is detected.

The trigger input detection unit 17 detects a trigger cancellation whenthe driver operates the trigger cancellation unit 8 b (for example, whenthe lever-type trigger cancellation unit 8 b is operated). The triggerinput detection unit 17 may be capable of detecting plural types oftrigger cancellation. The trigger input detection unit 17 may detect thetrigger cancelation when it is detected that the amount of operation(amount of depression) of the brake pedal is equal to or larger than acertain amount. The trigger input detection unit 17 may detect thetrigger cancellation when the driver slightly presses the autonomousdriving end button.

The traffic signal recognition unit 18 detects a lighting state of thetraffic signal located in the target point and is corresponding to thetraveling route (traveling lane) of the vehicle based on the result ofdetection (imaging information by the camera) performed by the externalsensor 2. The traffic signal recognition unit 18 can recognize thelighting state of the traffic signal from the imaging information by thecamera using image analysis processing. The traffic signal recognitionunit 18 may detect a lighting portion of the traffic signal usingtemplate matching, and then, may recognize the lighting state of thetraffic signal using a color recognition. The traffic signal recognitionunit 18 may detect the lighting portion of the traffic signal using thetemplate matching, and then, may recognize the lighting state of the“arrow” signal using a pattern recognition. The traffic signalrecognition unit 18 may refer to the map information in detecting theposition of the traffic signal. Specifically, the traffic signalrecognition unit 18 may acquire a position of a candidate of thelighting portion (a valve) of the traffic signal from the map database4, and then, may recognize the lighting state of the traffic signalusing the color recognition. In addition, in detecting the positionand/or the lighting portion of the traffic signal, the traffic signalrecognition unit 18 may use the object information detected by the radarsensor.

The lighting state of the traffic signal includes at least the passingpermitted state and the passing prohibited state. The passing permittedstate is a lighting state in which the vehicle is permitted to pass. Thepassing permitted state corresponds to a green signal in Japan. Thepassing prohibited state is a lighting state in which the vehicleprohibited to pass. The passing prohibited state corresponds to, forexample, a red signal in Japan. The lighting state of the traffic signalmay include a transition state which is a state during the transitionfrom the passing permitted state to the passing prohibited state. Thetransition state corresponds to, for example, a yellow signal in Japan.The lighting state of the traffic signal may include the passingpermitted state and the passing prohibited state for a specifictraveling direction indicated by an arrow signal. When the vehicle ispositioned on the lane corresponding to the arrow signal of the trafficsignal, the meaning of lighting state of the traffic signal changesaccording to the arrow signal.

In addition, the traffic signal recognition unit 18 recognizes theswitching of the lighting state of the traffic signal based on theresult of detection (imaging information by the camera) performed by theexternal sensor 2. The traffic signal recognition unit 18 recognizesthat the traffic signal is switched from the passing permitted state tothe passing permitted state. The traffic signal recognition unit 18 mayrecognize the lighting state of the traffic signal and the switching ofthe lighting state of the traffic signal not only by the imaginginformation by the camera but also through a wireless network connectedto the server or the like for managing the traffic information. Thetraffic signal recognition unit 18 may recognize the lighting state ofthe traffic signal by referring to a result of recognition of thetraffic signal by another vehicle through a vehicle-to-vehiclecommunication.

The vehicle control unit 19 performs the autonomous driving of thevehicle. The vehicle control unit 19 performs the autonomous driving ofthe vehicle based on the map information in the map database 4, theposition of the vehicle on the map recognized by the vehicle positionrecognition unit 11, the external environment of the vehicle recognizedby the external environment recognition unit 12, the traveling state ofthe vehicle recognized by the travel state recognition unit 13, and theroute generated by the route generation unit 15. The vehicle controlunit 19 performs the autonomous driving of the vehicle by transmittingthe control signal to the actuator 9.

If the trigger input request unit 16 performs the trigger input requestto the driver, and if the driver's trigger input is detected by thetrigger input detection unit 17, the vehicle control unit 19 causes theautonomously driving vehicle to pass through the target point. Thevehicle control unit 19 causes the vehicle to pass through the targetpoint by autonomous driving along the passing route.

Specifically, if the trigger input request is performed on the driver,the vehicle control unit 19 switches the route of the autonomouslydriving vehicle to the stop route. When the driver's trigger input isdetected, the vehicle control unit 19 returns the route of theautonomously driving vehicle from the stop route to the passing route,and causes the vehicle to pass through the target point.

When the driver's trigger input is detected before the deceleration ofthe vehicle is started on the stop route, the vehicle control unit 19causes the vehicle to pass through the target point without performingthe deceleration of the vehicle. The deceleration of the vehicle heremeans the deceleration to cause the vehicle to stop without passingthrough the target point. The vehicle control unit 19 may perform thedeceleration necessary for passing through the target point (forexample, deceleration for the right/left turn in the intersection).

If the driver's trigger input is not detected by the trigger inputdetection unit 17 despite that the trigger input request unit 16performed the trigger input request on the driver, the vehicle controlunit 19 decelerates and stops the autonomously driving vehicle withoutpassing through the target point.

The case where the trigger input is not detected means a case where, forexample, the trigger input is not detected until the vehicle reaches thebrake start position on the stop route. The case where the trigger inputis not detected may be a case where the trigger input is not detectedwhile the vehicle travels a certain distance set in advance after thetrigger input request is performed. Alternatively, the case where thetrigger input is not detected may be a case where the trigger input isnot detected within a certain time set in advance after the triggerinput request is performed.

Specifically, when the trigger input request is performed on the driver,the vehicle control unit 19 switches the route of the autonomouslydriving vehicle to the stop route. When the vehicle reaches the brakestart position on the stop route while the trigger input is notdetected, the vehicle control unit 19 notifies the driver of the startof deceleration of the vehicle (deceleration start notification) andcauses the vehicle to decelerate and stop without passing through thetarget point. For example, the vehicle control unit 19 causes thevehicle to stop at the position of the stop line before the passingpoint without passing through the target point. Hereinafter, thefunction of controlling the vehicle according to the trigger input willbe described with reference to the drawings.

Basic Function for Target Point where there is Traffic Signal

FIG. 2A is a plan view illustrating a situation in which a vehicleapproaches an intersection where a traffic signal is in a passingpermitted state. In FIG. 2A, the vehicle has a traveling route for goingstraight through the intersection. In FIG. 2A, an autonomously drivingvehicle M, a stop line 30, an intersection 40, and a traffic signal 50are illustrated.

The stop line 30 is a stop line corresponding to the intersection 40 onthe traveling route for the autonomous driving of the vehicle M. Theintersection 40 is a target point where there is a traffic signalpositioned on the traveling route for the autonomous driving of thevehicle M.

The traffic signal 50 is a traffic signal installed in the intersection40 and is corresponding to the traveling route of the vehicle M. In FIG.2A, the traffic signal 50 is in the passing permitted state, and theautonomous driving system 100 (the traffic signal recognition unit 18)also recognizes the passing permitted state.

FIG. 2B is a graph illustrating a vehicle speed profile when the triggerinput is detected. In FIG. 2B, the vertical axis represents the vehiclespeed and the horizontal axis represents the position. In FIG. 2B, atrigger request position Pa, a brake start position Pb, a stop lineposition Ps, a vehicle passing speed profile Va, and a vehicle stopspeed profile Vb are illustrated. In addition, the vehicle speed whenthe vehicle M actually travels is indicated as V.

The trigger request position Pa is a position at which it is determinedby the position determination unit 14 that the vehicle M approaches theintersection 40. The brake start position Pb is a position at which thedeceleration of the vehicle M is started on the stop route for causingthe vehicle M to stop without passing through the intersection 40. Thestop line position Ps is a position on the stop line 30 and the positionwhere the vehicle M stops on the stop route.

The vehicle passing speed profile Va is a vehicle speed profile forcausing the autonomously driving vehicle M to pass through theintersection 40. As an example, the vehicle passing speed profile Va isa vehicle speed profile for passing through the intersection 40 at aconstant speed. The vehicle stop speed profile Vb is a vehicle speedprofile for causing the autonomously driving vehicle M to decelerate andstop at the stop line position Ps before the intersection 40. Thevehicle passing speed profile Va and the vehicle stop speed profile Vbare the same until the vehicle M reaches the brake start position Pb. InFIG. 2A, the passing path and the stop path are assumed to be the same.

In the situation illustrated in FIG. 2A and FIG. 2B, in the autonomousdriving system 100, when the vehicle M reaches the trigger requestposition Pa, the position determination unit 14 determines that thevehicle M approaches the intersection 40, and the trigger input requestunit 16 performs the trigger input request on the driver. When thetrigger input request is performed, the vehicle control unit 19 startsthe autonomous driving along the vehicle stop speed profile Vb (stoproute).

Thereafter, since the driver's trigger input is detected by the triggerinput detection unit 17 before the vehicle M reaches the brake startposition Pb, the vehicle control unit 19 returns the driving to thevehicle passing speed profile Va (passing route). The vehicle controlunit 19 causes the vehicle M to pass through the target point along thevehicle passing speed profile Va. The vehicle speed V of the vehicle Mis coincident with the vehicle passing speed profile Va.

FIG. 3A is a plan view illustrating a situation in which the vehicleapproaches the intersection where the traffic signal is in the passingprohibited state. In FIG. 3A, the traffic signal 50 is in the passingprohibited state, and the autonomous driving system 100 also recognizesthe passing prohibited state. FIG. 3B is a graph illustrating thevehicle speed profile when the trigger input is not detected.Hereinafter, the same reference numerals are given to the sameconfiguration elements, and the description thereof will not berepeated.

In the situation illustrated in FIG. 3A and FIG. 3B, in the autonomousdriving system 100, the trigger input is not detected after the triggerinput request is performed on the driver. In this case, the vehiclecontrol unit 19 causes the vehicle M to performs autonomous drivingalong the vehicle stop speed profile Vb (stop route). If the vehicle Mreaches the brake start position Pb, the vehicle control unit 19 startsthe deceleration of the vehicle M according to the vehicle stop speedprofile Vb. Thereafter, the vehicle control unit 19 stops thedecelerated vehicle M at the stop line position Ps according to thevehicle stop speed profile Vb. The vehicle speed V of the vehicle M inthis case coincides with the vehicle stop speed profile Vb.

Trigger Cancellation Function

Even if the trigger input by the driver is detected, the vehicle controlunit 19 cancels the trigger input when the trigger cancellation by thedriver is detected by the trigger input detection unit 17.

Specifically, when the trigger cancelation is detected, the vehiclecontrol unit 19 determines whether or not the vehicle can stop in time,based on the position of the vehicle on the map, the stop position ofthe vehicle on the stop route, and the traveling state of the vehicle.To stop the vehicle in time means that the vehicle can stop at thescheduled stop position on the stop route at the deceleration equal toor lower than the allowable deceleration. The allowable deceleration isa deceleration set in advance. The allowable deceleration can be set asan upper limit of the deceleration which is an unnatural sudden brakingfrom the viewpoint of traffic flow, for example. The vehicle controlunit 19 determines that the vehicle can stop in time if the vehicle doesnot reach the brake start position on the stop route.

If it is determined that the vehicle can stop in time, the vehiclecontrol unit 19 cancels the trigger input. Thereafter, when the triggerinput is not detected, the vehicle control unit 19 causes the vehicle todecelerate along the stop route and to stop without passing through thetarget point.

Even if the vehicle travels along the passing route and exceeds thebrake start position after the trigger input is detected, when thetrigger cancellation is detected and it is determined that the vehiclecan stop in time, the vehicle control unit 19 shifts the route from thepassing route to the stop route. The vehicle control unit 19 shifts thevehicle speed from the vehicle passing speed profile Va to the vehiclestop speed profile Vb such that the vehicle speed V changes smoothly.

If it is determined that the vehicle cannot stop in time, the vehiclecontrol unit 19 notifies the driver that the trigger cancellation is notpossible. The vehicle control unit 19 notifies that the triggercancellation is not possible by transmitting the control signal to theHMI 8 and outputting a voice and/or an image. Instead of the imageoutput by the display, the lamp or the like of the instrument panel maybe turned on or blinked. In this case, the vehicle control unit 19 maydecelerate or accelerate the vehicle M according to the externalenvironment.

FIG. 4A is a plan view illustrating a situation in which the vehicleapproaches the intersection where the traffic signal is in the passingpermitted state. In FIG. 4A, the traffic signal 50 is in the passingpermitted state, and the autonomous driving system 100 also recognizesthe passing permitted state. FIG. 4B is a graph illustrating the vehiclespeed profile when the trigger cancellation is detected after thetrigger input.

In FIG. 4A and FIG. 4B, in the autonomous driving system 100, thetrigger input is detected after the trigger input request was performedon the driver, but thereafter the trigger cancellation is detected. Inthis case, since the trigger cancellation is detected before the vehicleM reaches the brake start position Pb, the vehicle control unit 19determines that the vehicle M can stop in time.

The vehicle control unit 19 shifts the route from the passing route tothe stop route, and causes the vehicle M to decelerate along the vehiclestop speed profile Vb and to stop at the stop line position Ps. In thiscase, the vehicle speed V of the vehicle M coincides with the vehiclestop speed profile Vb. The trigger cancellation can also be performedfor trigger input re-request (trigger input after the re-request of thetrigger input) which will be described later.

Returning Function by Trigger Input after Starting Deceleration

Even if the deceleration of the vehicle along the stop route is started,when the trigger input is detected, the vehicle control unit 19 stopsthe deceleration on the stop route and causes the vehicle to passthrough the target point. That is, the vehicle control unit 19 returnsfrom the stop route to the passing route. The vehicle control unit 19performs the returning from the passing route to the stop route suchthat the vehicle speed changes smoothly.

FIG. 5A is a plan view illustrating a situation in which the vehicleapproaches the intersection where the traffic signal is in the passingpermitted state. In FIG. 5A, the traffic signal 50 is in the passingpermitted state, and the autonomous driving system 100 also recognizesthe passing permitted state. FIG. 5B is a graph illustrating the vehiclespeed profile if the trigger input is detected the after deceleration ofthe vehicle starts.

In the situation illustrated in FIG. 5A and FIG. 5B, in the autonomousdriving system 100, the trigger input is not detected until the vehicleM reaches the brake start position Pb, and the deceleration of thevehicle M starts along the stop route. In this case, the vehicle controlunit 19 performs the autonomous driving such that the speed returns tothe vehicle passing speed profile Va from the vehicle stop speed profileVb. The vehicle control unit 19 controls the vehicle M such that thevehicle speed V changes smoothly from the vehicle stop speed profile Vbto the vehicle passing speed profile Va.

Re-Request Function when Traffic Signal is not Recognized as PassingPermitted State

Even if the trigger input by the driver is detected, when the trafficsignal recognition unit 18 recognizes that the traffic signal is not inthe passing permitted state, the trigger input request unit 16 notifiesthe driver that the traffic signal is recognized as not being in thepassing permitted state, and performs the trigger input re-request.

If the traffic signal is recognized as being in the passing prohibitedstate rather than in the passing permitted state, as a notification thatthe traffic signal is recognized as not being in the passing permittedstate, the trigger input request unit 16 performs a passing prohibitedstate recognition notification to notify that the traffic signal is inthe passing prohibited state. If the traffic signal is recognized asbeing in the transition state rather than in the passing permittedstate, as a notification that the traffic signal is recognized as notbeing in the passing permitted state, the trigger input request unit 16performs a transition state recognition notification to notify that thetraffic signal is in the transition state.

The trigger input request unit 16 performs the notification andre-request on the driver by transmitting a control signal to the HMI 8and outputting a voice from the speaker of the HMI 8. For example, thetrigger input request unit 16 notifies the driver that the trafficsignal is recognized as not the passing permitted state by outputting avoice saying “a red signal (passing prohibited state) is recognized”. Inaddition, the trigger input request unit 16 performs the trigger inputre-request on the driver by, for example, outputting a voice saying“Please check the traffic signal and re-input the trigger input if youwant the vehicle to pass”.

In addition, in the trigger input re-request, the trigger input requestunit 16 requests the driver to perform an input of which the type isdifferent from that of the trigger input before re-request. The triggerinput request unit 16 requests the driver to perform an input of whichthe type is different from that of the trigger input before re-requestamong the trigger input by operation of the trigger input unit 8 a, thetrigger input by the operation of the accelerator pedal, the triggerinput by touching the steering touch sensor 6, and other trigger inputsuch as the combinations of above-described trigger inputs. If the inputtype requested to the driver is performed in the trigger inputre-request by the trigger input request unit 16, the trigger inputdetection unit 17 detects the trigger input.

The trigger input request unit 16 may request the trigger input as there-request, in which the intention of the driver to input the trigger isclear compared to the trigger input before the re-request. If thetrigger input before the re-request is the operation of the acceleratorpedal larger than a certain amount, the trigger input request unit 16may request the trigger input by manually operating the lever-typetrigger input unit 8 a as the trigger input re-request. The triggerinput request unit 16 requests the driver to perform the trigger inputof which the type is different from that of the trigger input before there-request by outputting a voice saying “Please perform the re-input ofthe trigger by operating the lever-type trigger input unit”.

For example, if the trigger input before the re-request is a triggerinput by one input, the trigger input request unit 16 may request thedriver to perform a trigger input requiring multiple inputs as thetrigger input re-request, in which the intention of the driver to inputthe trigger is clear.

In addition, for example, if the trigger input before the re-request isthe trigger input by touching the steering touch sensor 6 by thedriver's both hands, as the trigger input request, the trigger inputrequest unit 16 may request the driver to perform the trigger input tooperate the accelerator pedal equal to or larger than a certain amountin the state in which the driver's both hands are in contact with thesteering touch sensor 6. In this way, the trigger input request unit 16can more reliably recognize the driver's decision by requesting theoperation that makes the driver's intention of trigger input clearer asthe trigger input re-request.

The trigger input request unit 16 may perform the notification or thetrigger input re-request by outputting the images by the display, or mayperform the notification or the trigger input re-request by both theimage output and the audio output. Instead of the image output by thedisplay, the lamp or the like of the instrument panel may be turned onor blinked. In addition, the trigger input request unit 16 may performthe trigger input re-request using the vibration of the steering wheeland/or the driver's seat as well.

Even if the trigger input by the driver is detected, if the trafficsignal recognition unit 18 recognizes that the traffic signal is in thepassing prohibited state, the vehicle control unit 19 causes the vehicleto keep the stop route. If the trigger input is detected after thetrigger input re-request is performed by the trigger input request unit16, the vehicle control unit 19 shifts the route from the stop route tothe passing route and causes the vehicle to pass through the targetpoint.

FIG. 6A is a plan view illustrating a situation in which the vehicleapproaches the intersection where the traffic signal is the passingprohibited state. In FIG. 6A, the traffic signal 50 is in the passingprohibited state, and the autonomous driving system 100 also recognizesthe passing prohibited state. FIG. 6B is a graph illustrating thevehicle speed profile when the trigger input re-request is performedafter the trigger input.

In the situation illustrated in FIG. 6A and FIG. 6B, in the autonomousdriving system 100, the trigger input by the driver is detected, butsince the traffic signal 50 is recognized as the passing prohibitedstate by the traffic signal recognition unit 18, the notification thatthe traffic signal 50 is not in the passing permitted state (the passingprohibited state recognition notification) and the trigger inputre-request is performed is performed on the driver. The driver receivesthe passing prohibited state recognition notification, and confirms thatthe traffic signal 50 is in the passing prohibited state, and then,determines to cause the vehicle M to stop. Since the trigger input bythe driver is not detected after the trigger input re-request, thevehicle control unit 19 causes the vehicle M to decelerate along thevehicle stop speed profile Vb and to stop at the stop line position Ps.

FIG. 7A is a plan view illustrating a situation where the vehicleapproaching the intersection where the traffic signal is in the passingpermitted state. In FIG. 7A, although the traffic signal 50 is in thepassing permitted state, but the autonomous driving system 100erroneously recognizes that the traffic signal 50 is in the passingprohibited state due to the influence of the backlight or the like. FIG.7B is a graph illustrating a vehicle speed profile if the trigger inputis detected after the trigger input re-request is performed.

In the situation illustrated in FIG. 7A and FIG. 7B, in the autonomousdriving system 100, since the trigger input by the driver is detectedbut the traffic signal 50 is erroneously recognized as the passingprohibited state by the traffic signal recognition unit 18, the passingprohibited state recognition notification and the trigger inputre-request are performed on the driver. In this case, the driver byreceives the passing prohibited state recognition notification andchecks the traffic signal 50, but determines that the traffic signal 50is in the passing permitted state and the recognition of the autonomousdriving system 100 is incorrect. The driver performs the re-input of thetrigger according to the trigger input re-request for causing thevehicle M to pass the intersection 40. Since the re-input of the triggerinput by the driver is detected, the vehicle control unit 19 causes thevehicle M to pass through the intersection 40 along the vehicle passingspeed profile Va.

Even if the first trigger input is not detected and the vehicle Mreaches the brake start position Pb and deceleration of the vehicle M isstarted, and thereafter the trigger input (the first trigger input) isdetected, when the traffic signal 50 is recognized as the passingprohibited state, the vehicle control unit 19 performs the passingprohibited state recognition notification and the trigger inputre-request.

In addition, if re-input of the trigger input is not detected after thevehicle re-request, the vehicle M reaches the brake start position Pb,and the deceleration of the vehicle M is started, then if trigger inputre-input is detected afterward, the vehicle control unit 19 may performthe same processing as the above-described “returning function by thetrigger input after the deceleration starting”.

Re-Request Function when Traffic Signal is Recognized as being Switchedto Other than Passing Permitted State

Even if the trigger input by the driver is detected, and if the trafficsignal recognition unit 18 recognizes that the traffic signal isswitched to a state other than the passing permitted state, the triggerinput request unit 16 notifies the driver that the traffic signalrecognized as being switched to the state other than the passingpermitted state, and performs the trigger input re-request.

Switching the traffic signal to a state other than the passing permittedstate includes switching the traffic signal state to the transitionstate or the passing prohibited state. Switching the traffic signal to astate other than the passing permitted state does not include switchingthe traffic signal from the passing prohibited state to the passingpermitted state. Hereinafter, the notification of the recognition thatthe traffic signal is switched to a state other than the passingpermitted state is referred to as a traffic signal switchingnotification.

Specifically, if the trigger input by the driver is detected and thetraffic signal recognition unit 18 recognizes that the traffic signal isswitched to a state other than the passing permitted state, the triggerinput request unit 16 determines whether or not the vehicle can stop intime. The determination whether or not the vehicle can stop in time canbe performed in the same way as in the case of the trigger cancellationfunction described above. If it is determined that the vehicle cannotstop in time, the trigger input request unit 16 does not need to performany particular processing. If it is determined that the vehicle can stopin time, the trigger input request unit 16 performs the traffic signalswitching notification and the trigger input re-request on the driver.

The trigger input request unit 16 performs the traffic signal switchingnotification and the re-request on the driver by transmitting a controlsignal to the HMI 8 and outputting a voice from the speaker of the HMI8. The trigger input request unit 16 performs the traffic signalswitching notification by outputting a voice saying, for example,“traffic signal is changed to the red signal (passing prohibitedstate)”.

In addition, the trigger input request unit 16 performs the triggerinput re-request on the driver by, for example, outputting a voicesaying “Please check the traffic signal and re-input the trigger inputif you want the vehicle to pass”. The trigger input re-request, can beperformed the same as that in the “Re-request Function when TrafficSignal is recognized as Passing Prohibited State”.

The re-input of the trigger input requested when the traffic signal isrecognized as being in the passing prohibited state and the re-input ofthe trigger input requested when the switching of the traffic signal isrecognized may be different types. In this case, if the input typerequested to the driver is performed in the trigger input re-request bythe trigger input request unit 16, the trigger input detection unit 17detects the trigger input.

Even if the trigger input by the driver is detected, if the trafficsignal recognition unit 18 recognizes the switching of the trafficsignal to the state other than the passing permitted state, the vehiclecontrol unit 19 causes the vehicle to keep the stop route. If thetrigger input is not detected after the trigger input re-request isperformed by the trigger input request unit 16, the vehicle control unit19 causes the vehicle to decelerate along the stop route and to stopwithout passing through the target point.

If the trigger input is detected before the vehicle reaches adeceleration start position to make the vehicle stop in time after thetrigger input re-request is performed, the vehicle control unit 19shifts the route from the stop route to the passing route and causes thevehicle to pass through the target point. The deceleration startposition is a position where the deceleration of the vehicle is requiredto stop the vehicle at the stop position on the stop route.

FIG. 8A is a plan view illustrating a situation in which the trafficsignal is switched to a state other than the passing permitted statewhile the vehicle approaches the intersection. In FIG. 8A, the trafficsignal 50 is in the passing permitted state, but is switched from thepassing permitted state to the transition state while the vehicle M isapproaching. The autonomous driving system 100 also recognizes theswitching of the traffic signal. FIG. 8B is a graph illustrating avehicle speed profile if the trigger input is detected after the triggerinput re-request is performed due to the switching of the trafficsignal.

In the situation illustrated in FIG. 8A and FIG. 8B, in the autonomousdriving system 100, since the traffic signal recognition unit 18recognizes that the traffic signal 50 is switched to the transitionstate after the trigger input by the driver is detected, the trafficsignal switching notification and the trigger input re-request areperformed on the driver. The driver receives the traffic signalswitching notification and confirms that the traffic signal 50 isswitched to the transition state. In FIG. 8B, the driver determines thatthe vehicle M can pass through the intersection 40 before the trafficsignal 50 is switched to the passing prohibited state, and thus,performs the re-inputs of the trigger input.

Since the re-input of the trigger input by the driver was detected, thevehicle control unit 19 causes the vehicle M to pass through theintersection 40 according to the vehicle passing speed profile Va. Inthis case, since the vehicle M is caused to pass through theintersection 40 before the traffic signal 50 is switched to the passingprohibited state, the vehicle control unit 19 may increase the vehiclespeed of the vehicle M within a vehicle speed range set in advance.

If the deceleration of the vehicle M is started before the vehicle Mreaches the brake start position Pb without the re-input of the triggerinput being detected, the vehicle control unit 19 may perform the sameprocessing as that in the above-described “Returning Function by TriggerInput after Starting Deceleration”.

In addition, when the re-input of the trigger input is performed afterthe traffic signal 50 is recognized as being switched from the passingpermitted state to the transition state, and thereafter, even if thetraffic signal 50 is recognized as being switched from the transitionstate to the passing prohibited state before the vehicle M passesthrough the intersection 40, the trigger input request unit 16 may notrepeatedly perform the traffic signal switching notification and thetrigger input re-request. In this case, after the re-input of triggerinput is performed by the driver, even if the traffic signal 50 isrecognized as being switched from the transition state to the passingprohibited state and the re-input of the trigger input is not performed,the vehicle control unit 19 may cause the vehicle M to pass through theintersection 40.

Second Request Function when Traffic Signal is Recognized as beingSwitched to Passing Permitted State

If the traffic signal recognition unit 18 recognizes that the trafficsignal is switched to the passing permitted state without the triggerinput by the driver being detected after the trigger input request isperformed, the trigger input request unit 16 notifies the driver thatthe switching of the traffic signal to the passing permitted state isrecognized and performs a second trigger input request.

A trigger input request that is performed in a state in which thetrigger input is not detected after the trigger input request isperformed is expressed as the second trigger input request. The triggerinput request unit 16 transmits a control signal to, for example, theHMI 8, notifies the driver that the traffic signal is recognized asbeing switched to the passing permitted state by the voice output fromthe speaker of the HMI 8, and performs the second trigger input request.The trigger input request unit 16 may perform the notification and thesecond trigger input request by outputting an image to the display.

FIG. 9A is a plan view illustrating a situation in which the trafficsignal is switched to the passing permitted state while the vehicleapproaches the intersection. In FIG. 9A, the traffic signal 50 is in thepassing prohibited state, but is switched from the passing prohibitedstate to the passing permitted state while vehicle M approaches theintersection. The autonomous driving system 100 also recognizes theswitching of the traffic signal. FIG. 9B is a graph illustrating avehicle speed profile when a first trigger input is detected after anotification of switching the traffic signal to the passing permittedstate after the deceleration of the vehicle starts while the triggerinput is not detected.

In the situation illustrated in FIGS. 9A and 9B, in the autonomousdriving system 100, the vehicle M reaches the brake start position Pband deceleration of the vehicle M is started while the trigger input isnot detected. Thereafter, since the traffic signal recognition unit 18recognizes that the traffic signal 50 is switched to the passingpermitted state while the trigger input is not detected, the triggerinput request unit 16 performs the traffic signal switching notification(notification that the traffic signal 50 is switched to the passingpermitted state in this case) and the second trigger input request onthe driver.

The driver did not perform the trigger input because, for example, thetraffic signal is recognized as being in the passing prohibited state,but after receiving the traffic signal switching notification that thetraffic signal is switched to the passing permitted state, and then,confirms that the traffic signal 50 is switched to the passing permittedstate and performs the trigger input. The vehicle control unit 19detects the trigger input by the driver, shifts the route from the stoproute to the passing route, and causes the vehicle M to pass through theintersection 40.

Basic Function for Target Point where there is No Traffic Signal.

FIG. 10A is a plan view illustrating a situation in which the vehicleattempts to turn right in the intersection where there is no trafficsignal. In FIG. 10A, an intersection (target point) 60 where there is notraffic signal, a pedestrian cross-walk 70 provided at a destination ofthe right turn of vehicle M at the intersection 60, a building 80positioned between the vehicle M and the pedestrian cross-walk 70 beforethe right turn in the intersection 60. There is no stop line in theintersection 60. FIG. 10B is a graph illustrating a vehicle speedprofile when the trigger input is detected.

In the situation illustrated in FIG. 10A and FIG. 10B, autonomousdriving system 100, since the detection range of the external sensor 2is obstructed by the building 80 at the stage before the vehicle Menters the intersection 60, it is not possible to detect the situationat the destination of the right turn in the intersection 60 (thesituation such as the presence or absence of pedestrians at thepedestrian cross-walk 70). In this situation, the route generation unit15 generates a vehicle stop speed profile Vc in which the vehicle M isstopped in the intersection 60. A waiting position Pt in the vehiclestop speed profile Vc is not particularly limited. The waiting positionPt can be a position at which the driver can visually recognize thesituation at the destination of the right turn. In this example, theroute generation unit 15 does not create a vehicle passing speedprofile, but may create a vehicle passing speed profile that makes thevehicle pass through the intersection 60 at a low speed.

In order for the right turn of the vehicle M, the vehicle control unit19 causes the vehicle M exceeding the brake start position Pb todecelerate the vehicle speed according to the vehicle stop speed profileVc. The position determination unit 14 determines that the vehicle Mapproaches the intersection 60 based on, for example, a distance betweenthe vehicle M and the intersection 60. If the position determinationunit 14 determines that the vehicle M approaches the intersection 60 (ifthe vehicle M reaches the trigger request position Pa), the triggerinput request unit 16 performs the trigger input request on the driver.

The trigger input request unit 16 performs the trigger input request by,for example, transmitting a control signal to the HMI 8, and outputtinga voice saying “Please check the traveling direction (or right turningdirection) of the vehicle in the intersection, and if passing ispermitted, please perform the trigger input”. The driver looks at thetraveling direction in the intersection according to the trigger inputrequest, confirms that there are no pedestrians or the like at thepedestrian cross-walk 70, and then, performs the trigger input. When thetrigger input by the driver is detected, the vehicle control unit 19increases the vehicle speed and causes the vehicle M to pass through theintersection 60. The vehicle control unit 19 causes the vehicle M topass through the intersection 60 at the speed corresponding to the rightturn in the intersection according to traffic rules.

FIG. 11A is a plan view illustrating a situation in which the vehicleattempts to turn right in the intersection where there is no trafficsignal. FIG. 11A illustrates the same situation as FIG. 10A. FIG. 11B isa graph illustrating a vehicle speed profile when the trigger input isnot detected.

In the situation illustrated in FIG. 11A and FIG. 11B, in the autonomousdriving system 100, in order for the right turn of the vehicle M, thevehicle speed of the vehicle M exceeding the brake start position Pb isdecelerated along the vehicle stop speed profile Vc. The trigger inputrequest unit 16 performs the trigger input request on the driver whenthe vehicle M reaches the trigger request position Pa. Since the triggerinput by the driver is not detected, the vehicle control unit 19 causesthe vehicle M to stop at the waiting position Pt according to thevehicle stop speed profile Vc.

If the intersection where there is no traffic signal is the targetpoint, the route generation unit 15 does not necessarily need to set thewaiting position Pt within the intersection. The route generation unit15 may set the waiting position Pt before the intersection. The routegeneration unit 15 may individually set the waiting position Ptaccording to the traveling route. The route generation unit 15 mayindividually set the waiting position Pt according to the travelingroute such that the traveling direction of vehicle M (right turn, leftturn, straight ahead or the like) in the intersection where there is notraffic signal becomes a position visible to the driver. If there is astop line before the intersection in the situation illustrated in FIG.10A, the route generation unit 15 may cause the vehicle M to stop at thestop line.

Control Method of Autonomous Driving System

Next, a control method of the autonomous driving system 100 will bedescribed with reference to the drawings.

Stop Route Generation Processing

FIG. 12 is a flowchart illustrating the stop route generationprocessing. The processing in the flowchart illustrated in FIG. 12 isperformed when the vehicle is in the autonomous driving.

As illustrated in FIG. 12 , as S10, the ECU 10 of the autonomous drivingsystem 100 determines whether or not the distance between theautonomously driving vehicle and the target point is equal to or shorterthan the route generation threshold value using the positiondetermination unit 14. The position determination unit 14 determineswhether or not the distance between the vehicle and the target point isequal to or shorter than the route generation threshold value based onthe position of the vehicle on the map, the map information and thetraveling route for the autonomous driving. If it is determined that thedistance between the autonomously driving vehicle and the target pointis equal to or shorter than the route generation threshold value (YES inS10), the ECU 10 makes the process proceed to S12. If it is notdetermined that the distance between the autonomously driving vehicleand the target point is equal to or shorter than the route generationthreshold value (NO in S10), the ECU 10 ends the current processing.Thereafter, the ECU 10 repeats the processing from S10 again after acertain time elapsed.

In S12, the ECU 10 generates the stop route using the route generationunit 15. The stop route includes the stop path and the vehicle stopspeed profile. The route generation unit 15 generates the stop pathbased on, for example, the traveling route, the map information, theexternal environment of the vehicle, and the traveling state of thevehicle. The route generation unit 15 generates the vehicle stop speedprofile based on the information such as the legal speed (or any setspeed) included in path and the map information, for example. The routegeneration unit 15 generates the stop route according to the targetpoint.

When using the path same as the passing route generated in the past asthe stop route, the route generation unit 15 may generate only thevehicle stop speed profile. When the stop route is generated, the ECU 10ends the stop route generation processing for the current target point.

Trigger Input Detection Processing for Target Point where there isTraffic Signal

FIG. 13 is a flowchart illustrating the trigger input detectionprocessing for the target point where there is a traffic signal. Theprocessing in the flowchart illustrated in FIG. 13 is performed when thestop route for the target point where there is a traffic signal isgenerated and the vehicle is in the autonomous driving.

As illustrated in FIG. 13 , as S20, the ECU 10 determines whether or notthe autonomously driving vehicle approaches the target point where thereis a traffic signal using the position determination unit 14. Theposition determination unit 14 determines whether or not theautonomously driving vehicle approaches the target point where there isa traffic signal based on the position of the vehicle on the map, themap information, and the traveling route for the autonomous driving.

If it is determined that the autonomously driving vehicle approaches thetarget point where is a traffic signal (YES in S20), the ECU 10 makesthe process proceed to S22. If it is not determined that theautonomously driving vehicle approaches the target point where is atraffic signal (NO in S20), the ECU 10 ends the current processing.Thereafter, the ECU 10 repeats the processing from S20 after a certaintime elapsed.

In S22, the ECU 10 performs a trigger input request on the driver usingthe trigger input request unit 16 (trigger input request step). Thetrigger input request unit 16 performs the trigger input request on thedriver by transmitting the control signal to the HMI 8 and outputting avoice from the speaker of the HMI 8. Thereafter, the ECU 10 makes theprocess proceed to S24.

In S24, the ECU 10 determines whether or not the trigger input isdetected using the trigger input detection unit 17 (trigger inputdetection step). The trigger input detection unit 17 detects at leastone of the trigger input among the input by the operation of the triggerinput unit 8 a by the driver, the input by the accelerator operation,the input by touching the steering touch sensor 6, and the like. Whenthe trigger input is detected (YES in S24), the ECU 10 makes the processproceed to S28. When the trigger input is not detected (NO in S24), theECU 10 makes the process proceed to S26.

In S26, the ECU 10 determines whether or not the vehicle reaches thebrake start position using the vehicle control unit 19. The vehiclecontrol unit 19 determines whether or not the vehicle reaches the brakestart position based on the stop route (the vehicle stop speed profile)and the position of the vehicle on the map. If it is determined that thevehicle reaches the brake start position (YES in S26), the ECU 10 makesthe process proceed to S38. If it is not determined that the vehiclereaches the brake start position (NO in S26), the ECU 10 makes theprocess return to S24 and determines again whether or not the triggerinput is detected.

In S28, the ECU 10 determines whether or not the traffic signal locatedin the target point is in the passing permitted state (traffic signalrecognition step) using the traffic signal recognition unit 18. Thetraffic signal recognition unit 18 determines whether or not the trafficsignal is in the passing permitted state based on the result ofdetection performed by the external sensor 2. If it is determined thatthe traffic signal is in the passing permitted state (YES in S28), theECU 10 makes the process proceed to S34. If it is not determined thatthe traffic signal is in the passing permitted state (NO in S28), theECU 10 makes the process proceed to S30.

In S30, the ECU 10 performs the notification that the traffic signal 50is recognized as not being in the passing permitted state and thetrigger input re-request on the driver using the trigger input requestunit 16 (first re-request step). The trigger input request unit 16performs the notification and the re-requests on the driver by, forexample, transmitting a control signal to the HMI 8 and outputting avoice from the speaker of the HMI 8. The trigger input request unit 16requests the driver to perform the trigger input of which the type isdifferent from that of the trigger input before the re-request.Thereafter, the ECU 10 makes the process proceed to S32.

In S32, the ECU 10 determines whether or not the re-input of the triggerinput is detected using the trigger input detection unit 17 (triggerinput detection step). If the input type requested to the driver isperformed in the trigger input re-request by the trigger input requestunit 16, the trigger input detection unit 17 detects the trigger input.When the trigger input is detected (YES in S32), the ECU 10 makes theprocess proceed to S34. When the trigger input is not detected (NO inS32), the ECU 10 makes the process proceed to S36.

In S 34, the ECU 10 execute the passing route using the vehicle controlunit 19 (vehicle control step). The vehicle control unit 19 causes thevehicle to pass through the target point along the passing route bytransmitting a control signal to the actuator 9. If the trigger input isdetected before deceleration of the vehicle along the stop route isstarted, the vehicle control unit 19 causes the vehicle to pass throughthe target point along the passing route without performing thedeceleration of the vehicle along the stop route.

In S36, the ECU 10 determines whether or not the vehicle reaches thebrake start position using the vehicle control unit 19. If it isdetermined that the vehicle reaches the brake start position (YES inS36), the ECU 10 makes the process proceed to S38. If it is notdetermined that the vehicle reaches the brake start position (NO inS36), the ECU 10 makes the process returns to S32, and determines againwhether or not the trigger input is detected.

In S38, the ECU 10 notifies the driver of the deceleration start usingthe vehicle control unit 19. The vehicle control unit 19 notifies thedriver of the deceleration start by transmitting a control signal to theHMI 8 and outputting a voice from the speaker of the HMI 8. Thereafter,the ECU 10 makes the process proceed to S40.

In S40, the ECU 10 executes the stop route using the vehicle controlunit 19 (vehicle control step). The vehicle control unit 19 causes thevehicle to decelerate along the stop route by sending a control signalto the actuator 9. If the trigger input is not detected thereafter, thevehicle control unit 19 causes the vehicle to stop without passingthrough the target point.

As described above, the trigger input detection processing for thetarget point where there is a traffic signal was described, however, inthe processing in S26, it may not be determined whether or not thevehicle reaches the brake start position but may be determined whetheror not a first set time set in advance has elapsed from the triggerinput request. Similarly, in the process in S36 also, it may bedetermined whether or not a second setting time set in advance haselapsed from the trigger input re-request. The first set time and thesecond set time can be respectively a sufficient time for the driver tocheck the traffic signal and determine whether the trigger input isnecessary or not. In addition, the first set time and the second settime can be respectively set as a time equal to or shorter than aremaining time for the vehicle to reach the brake start position.

Furthermore, the processing in the flowchart illustrated in FIG. 13 endswhen the autonomous driving ends even during the processing. This pointis the same to the processing items as in FIG. 14 to FIG. 17 .

Additional Processing after Trigger Input

FIG. 14 is a flowchart illustrating additional processing after thetrigger input. The processing in the flowchart illustrated in FIG. 14 isperformed, for example, if the trigger input is detected in S24 in FIG.13. The processing in the flowchart illustrated in FIG. 14 may beperformed if the trigger input is detected in S94 in FIG. 17 describedlater. The processing in the flowchart illustrated in FIG. 14 ends ifthe vehicle is stopped along the stop route or if the vehicle passesthrough the target point even during the processing.

As illustrated in FIG. 14 , as S50, the ECU 10 determines whether or notthe trigger cancelation is detected using the trigger input detectionunit 17 (trigger cancelation detection step). For example, when thedriver operates the trigger cancellation unit 8 b, the trigger inputdetection unit 17 detects the trigger cancellation. If the triggercancelation is detected (YES in S50), the ECU 10 makes the processproceed to S52. If the trigger cancelation is not detected (NO in S50),the ECU 10 makes the current processing end. Thereafter, the ECU 10repeats the processing from S50 again after a certain time elapsed.

In S52, the ECU 10 determines whether or not the vehicle can stop intime using the vehicle control unit 19. The vehicle control unit 19determines whether or not the vehicle can stop in time based on the stopposition of the vehicle on the map, the stop position of the vehicle onthe stop route, and the traveling state of the vehicle. If it isdetermined that the vehicle can stop in time (YES in S52), the ECU 10makes the process proceed to S54. If it is determined that the vehiclecannot stop in time (NO in S52), the ECU 10 makes the process proceed toS56.

In S54, the ECU 10 performs the trigger cancellation processing usingthe vehicle control unit 19. If the vehicle does not reach the brakestart position, the vehicle control unit 19 cancels the trigger inputand returns to the process to S24 in FIG. 13 . If the vehicle hasalready passed the brake start position and approaches the target pointalong the passing route, the vehicle control unit 19 cancels the triggerinput and shifts the route from the passing route to the stop route.

In S56, the ECU 10 notifies the driver that the trigger cancellation isnot possible using the vehicle control unit 19. The vehicle control unit19 notifies that the trigger cancellation is not possible bytransmitting the control signal to the HMI 8 and outputting a voiceand/or the image.

Additional Processing when Passing Route is Executed

FIG. 15 is a flowchart illustrating the additional processing when thepassing route is executed. The processing in the flowchart illustratedin FIG. 15 is performed when the passing route is executed in S34 inFIG. 14 , S96 in FIG. 17 to be described later, or when the route isshifted from the stop route. The processing in the flowchart illustratedin FIG. 15 ends when the vehicle passes through the target point evenduring the processing.

As illustrated in FIG. 15 , as S60, the ECU 10 determines whether or notthe traffic signal recognition unit 18 recognizes that the trafficsignal is switched to a state other than the passing permitted state(traffic signal recognition step). The traffic signal recognition unit18 determines whether or not the traffic signal is switched to a stateother than the passing permitted state based on the result of detectionperformed by the external sensor 2, for example. If it is determinedthat the switching of the traffic signal to the state other than thepassing permitted state is recognized (YES in S60), the ECU 10 makes theprocess proceed to S62. If it is not determined that the switching ofthe traffic signal to the state other than the passing permitted stateis recognized (NO in S60), the ECU 10 makes the process proceed to S60.Thereafter, the ECU 10 repeats the processing again from S60.

In S62, the ECU 10 determines whether or not the vehicle can stop intime using the vehicle control unit 19. If it is determined that thevehicle can stop in time (YES in S62), the ECU 10 makes the processproceed to S64. If it is determined that the vehicle cannot stop in time(NO in S62), the ECU 10 ends the passing processing when the passingroute is executed.

In S64, the ECU 10 notifies the driver that the switching of the trafficsignal to the state other than the passing permitted state isrecognized, and performs the trigger input re-request using the triggerinput request unit 16 (second re-request step). The trigger inputrequest unit 16 performs the traffic signal switching notification andre-request on the driver by transmitting a control signal to the HMI 8and outputting a voice from the speaker of the HMI 8. The trigger inputrequest unit 16 request the driver to perform the trigger input of whichthe type is different from that of the trigger input before there-request. Thereafter, the ECU 10 makes the process proceed to S66.

In S66, the ECU 10 determines whether or not the trigger input isdetected by the trigger input detection unit 17 (trigger input detectionstep). If the input type requested to the driver is performed in thetrigger input re-request by the trigger input request unit 16, thetrigger input detection unit 17 detects the trigger input. If thetrigger input is detected (YES in S66), the ECU 10 ends the passingprocess when the passing route is executed. If the trigger input is notdetected (NO in S66), the ECU 10 makes the process proceed to S68.

In S 68, the ECU 10 determines whether or not the vehicle reaches thedeceleration start position using the vehicle control unit 19. Thevehicle control unit 19 determines whether or not the vehicle reachesthe deceleration start position based on the stop position on the stoproute, the position of the vehicle on the map, and the traveling stateof the vehicle. If it is determined that the vehicle reaches thedeceleration start position (YES in S68), the ECU 10 makes the processproceed to S70. If it is not determined that the vehicle reaches thedeceleration start position (NO in S68), the ECU 10 makes the processreturn to S66 and repeats the trigger input detection.

In S70, the ECU 10 notifies the driver of the deceleration start usingthe vehicle control unit 19. The vehicle control unit 19 notifies thedriver of the deceleration start by transmitting a control signal to theHMI 8 and outputting a voice from the speaker of the HMI 8. Thereafter,the ECU 10 makes the process proceed to S72.

In S72, the ECU 10 shifts the route from the passing route to the stoproute using the vehicle control unit 19 (vehicle control step). Thevehicle control unit 19 causes the vehicle to decelerate by shifting theroute from the passing route to the stop route, and to stop withoutpassing through the target point.

Additional Processing when Stop Route is Executed

FIG. 16 is a flowchart illustrating the additional processing when thestop route is executed. The processing in the flowchart illustrated inFIG. 16 is performed when the stop route is executed in S40 in FIG. 13 ,S98 in FIG. 17 to be described later, or when the route is switched fromthe passing route. The processing in the flowchart illustrated in FIG.16 ends the vehicle is stopped even during the processing.

As illustrated in FIG. 16 , as S80, the ECU 10 determines whether or notthe traffic signal recognition unit 18 recognizes that the trafficsignal is switched to the passing permitted state (traffic signalrecognition step). If it is determined that the switching of the trafficsignal to the passing permitted state is recognized (YES in S80), theECU 10 makes the process proceed to S82. If it is determined that thetraffic signal is not recognized as being switched to the passingpermitted state (NO in S80), the ECU 10 makes the process proceed toS84.

In S82, the ECU 10 notifies the driver that the traffic signal isswitched to the passing permitted state and performs the second triggerinput request using the trigger input request unit 16 (second triggerinput request step). Thereafter, the ECU 10 makes the process proceed toS84.

In S84, the ECU 10 determines whether or not the trigger input isdetected by the trigger input detection unit 17 (trigger input detectionstep). If it determined that the trigger input is detected (YES in S84),the ECU 10 makes the process proceed to S86. If it determined that thetrigger input is not detected (NO in S84), the ECU 10 ends the currentprocessing. Thereafter, the ECU 10 repeats the processing again fromS80.

In S86, the ECU 10 shifts the route from the stop route to the passingroute using the vehicle control unit 19 (vehicle control step). Thevehicle control unit 19 causes the vehicle to pass through the targetpoint by shifting the route from the stop route to the passing route.

Trigger Input Detection Processing for the Target Point where there isNo Traffic Signal

FIG. 17 is a flowchart illustrating the trigger input detectionprocessing for the target point where there is no traffic signal. Theprocessing in the flowchart illustrated in FIG. 17 is performed when thestop route for the target point where there is no traffic signal isgenerated and the vehicle is in the autonomous driving.

As illustrated in FIG. 17 , as S90, the ECU 10 determines whether or notthe autonomously driving vehicle approaches the target point where thereis no traffic signal using the position determination unit 14. Theposition determination unit 14 determines whether or not theautonomously driving vehicle approaches the target point where there isno traffic signal based on the position of the vehicle on the map, themap information, and the traveling route for the autonomous driving.

If it is determined that the autonomously driving vehicle approaches thetarget point where is no traffic signal (YES in S90), the ECU 10 makesthe process proceed to S92. If it is not determined that theautonomously driving vehicle approaches the target point where is notraffic signal (NO in S90), the ECU 10 ends the current processing.Thereafter, the ECU 10 repeats the processing again from S90 after acertain time elapsed.

In S92, the ECU 10 performs a trigger input request on the driver usingthe trigger input request unit 16 (trigger input request step). Thetrigger input request unit 16 performs the trigger input request on thedriver by transmitting a control signal to the HMI 8 and outputting avoice from the speaker of the HMI 8. Thereafter, the ECU 10 makes theprocess proceed to S94.

In S94, the ECU 10 determines whether or not the trigger input isdetected using the trigger input detection unit 17 (trigger inputdetection step). If it is determined that the trigger input is detected(YES in S94), the ECU 10 makes the process proceed to S96. If it is notdetermined that the trigger input is detected (NO in S94), the ECU 10makes the process proceed to S98.

In S96, the ECU 10 executes the passing route using the vehicle controlunit 19 (vehicle control step). The vehicle control unit 19 causes thevehicle to pass through the target point along the passing route.

In S98, the ECU 10 executes the stop route using the vehicle controlunit 19 (vehicle control step). The vehicle control unit 19 causes thevehicle to decelerate along the stop route and to stop at the targetpoint without passing through the target point. The vehicle control unit19 may notify the driver of the deceleration start before thedeceleration of the vehicle along the stop route starts.

Operational Effects of Autonomous Driving System and Control Method ofAutonomous Driving System

According to the autonomous driving system 100 and the control methodthereof according to the embodiment described above, if the autonomouslydriving vehicle approaches the target point such as an intersection, andthe driver is requested to perform the trigger input for the vehicle topass through the target point, the vehicle is caused to pass through thetarget point if the trigger input is detected, and the vehicle is causedto decelerate and stop at the target point without passing through thetarget point if the trigger input is not detected. Therefore, in theautonomous driving system 100 and the control method thereof, it ispossible to cause the vehicle to pass through the target point afterobtaining the driver's decision whether or not to pass through thetarget point.

In the autonomous driving system 100 and the control method thereof, thetrigger input request is performed before the deceleration of thevehicle starts, and if the trigger input is detected before thedeceleration of the vehicle starts, the vehicle is caused to passthrough the target point without performing the deceleration of thevehicle to stop. Therefore, according to the autonomous driving system100 and the control method thereof, the driver can perform the triggerinput earlier according to the trigger input request compared to a casewhere the vehicle is always decelerated toward the target point, andthus, it is possible to cause the vehicle to pass through the targetpoint without performing the deceleration of the vehicle to stop.

According to the autonomous driving system 100 and the control methodthereof, even if the deceleration of the vehicle to stop is started forstopping the vehicle without passing through the target point withoutthe trigger input being detected, since it is possible to cause thevehicle to stop the deceleration and to pass through the target point ifthe trigger input is detected, it is possible to cause the vehicle topass through the target point according to the driver's decision even ifthe driver's trigger input is delayed.

According to the autonomous driving system 100 and the control methodthereof, even if the driver performs the trigger input, when the trafficsignal recognition unit recognizes that the traffic signal is not in thepassing permitted state, since the trigger input re-request is performedby notifying the driver that the traffic signal is not in the passingpermitted state, it is possible to prevent the driver from performing anerroneous decision in the situation in which the traffic signalrecognition unit recognizes that the traffic signal is not in thepassing permitted state.

According to the autonomous driving system 100 and the control methodthereof, even if the driver performs the trigger input, when theswitching of the traffic signal to the state other than the passingpermitted state is recognized, the driver is notified that the switchingof the traffic signal to the state other than the passing permittedstate is recognized and the trigger input re-request is performed, thedriver can be notified that the traffic signal is switched to the stateother than the passing permitted state after the trigger input isperformed, and thus, it is possible for the driver to perform thedecision according to the situation.

According to the autonomous driving system 100 and the control methodthereof, in the trigger input re-request, since the driver is requestedto perform trigger input of which the type is different from that of thetrigger input before the re-request, it is possible to prevent thedriver from easily performing the trigger input without recognizing thesituation in which the trigger input is requested.

The preferred embodiments of the present disclosure are described above,however, the present disclosure is not limited to the above-describedembodiments. In addition to the above-described embodiments, the presentdisclosure can be embodied in various forms including variousmodifications and improvements based on the knowledge of those skilledin the art.

The trigger input detection unit 17 may detect the trigger input beforethe trigger input request. There is a possibility that the driver maymemorize the target point on the everyday traveling route, and mayperform the trigger input by recognizing the lighting state or the likeof the traffic signal at the target point earlier than a time thevehicle reaches the trigger request position. If a distance between theautonomously driving vehicle and the target point is equal to or shorterthan a trigger detection threshold value, the trigger input detectionunit 17 detects the trigger input before the trigger input request asthe trigger input for causing the vehicle to pass through the targetpoint in front of the vehicle. The trigger detection threshold value isa threshold value set in advance. The determination may be made by thearrival time to the target point instead of the distance. In this case,the trigger input detection unit 17 notifies the driver that the triggerinput for the vehicle to pass through the target point is detected, bytransmitting a control signal to the HMI 8 and outputting a voice and/oran image. Instead of the image output by the display, the lamp or thelike of the instrument panel may be turned on or blinked.

The position determination unit 14 may change the trigger requestposition according to a state of the driver. The position determinationunit 14 may determine whether or not the driver is concentrating on thedriving based on, for example, the contact information from the steeringtouch sensor 6 and the information of imaging the driver by the drivermonitor camera 7. Examples of the cases where the driver is notconcentrating on the driving are a case where the driver is stoking, acase where the driver does not grasp the steering wheel, and the like.An example of the case where the driver is concentrating on the drivingis a case where the driver holds the steering wheel with the face facingthe front of the vehicle, or the like. When it is determined that thedriver is not concentrating on driving, the position determination unit14 may set the trigger request position away from the target pointcompared to the case where it is determined that the driver isconcentrating on the driving. When it is determined that the driver isconcentrating on the driving, the trigger input request unit 16 may omitthe trigger input request.

The trigger input detection unit 17 does not necessarily need to detectmultiple types of trigger input. The trigger input detection unit 17 maydetect at least one of the input by the driver's manual operation on thetrigger input unit 8 a provided in the vehicle, the input by thedriver's accelerator operation on the accelerator pedal of the vehicle,or the input by touching the steering touch sensor 6, as the triggerinput. The touch sensor of the vehicle is not limited to the steeringtouch sensor 6, but may be a touch sensor provided in the instrumentpanel of the vehicle, a touch sensor provided in the armrest of thevehicle, or may be a touch sensor provided inside the door of thevehicle. In addition, in order to detect the driver's grip of thesteering wheel, a grip sensor incorporated in the steering wheel anddetecting the driver's grip of the steering wheel may be used. If it isdetected by the signal from the grip sensor that the gripping force ofdriver's both hands is equal to or larger than a certain thresholdvalue, the trigger input detection unit 17 may detect the trigger input.

In the trigger input re-request, the trigger input request unit 16 mayrequest the driver to perform the trigger input of which the type is thesame as that of the trigger input before re-request. The trigger inputrequest unit 16 requests the driver to perform the trigger input ofwhich the type is the same as that of the trigger input before there-request and an amount of operation is larger than that before there-request. If the button-type trigger input unit 8 a is operated as thetrigger input before the re-request, the trigger input request unit 16may request the driver to perform the operation of pushing a buttondeeply or pressing the button for a long time compared to that beforethe re-request, as the trigger input after the re-request. If thelever-type trigger input unit 8 a is operated as the trigger inputbefore the re-request, the trigger input request unit 16 may request thedriver to perform the operation of pulling down the lever largelycompared to that before the trigger re-request, as the trigger inputafter the re-request. If the accelerator pedal is operated as thetrigger input before the re-request, the trigger input request unit 16may request the driver to perform the operation of depressing theaccelerator pedal deeply or depressing the accelerator pedal for a longtime compared to that before the trigger re-request, as the triggerinput after the re-request.

The route generation unit 15 does not necessarily need to startgenerating the stop route based on the distance between the autonomouslydriving vehicle and the target point. The time to arrival may be usedinstead of the distance. The route generation unit 15 may generate thestop route at a timing at which the generation processing is possible,regardless of the distance between the autonomously driving vehicle andthe target point. The route generation unit 15 may generate the passingroute and the stop route at the same timing. The vehicle control unit 19may switch the route from the passing route to the stop route at thetime when the vehicle reaches the brake start position without thetrigger input being detected, not at the time when the trigger inputrequest is performed on the driver.

The autonomous driving system 100 does not necessarily need to have thefunction of trigger cancellation. If trigger input is erroneous, theautonomous driving system 100 may have a configuration in which thedriver ends the autonomous driving by operating the autonomous drivingend input unit.

The autonomous driving system 100 does not necessarily need to have thereturning function by the trigger input after the starting thedeceleration. If the vehicle reaches the brake start position withouttrigger input being detected, the autonomous driving system 100 may havea configuration in which in which the vehicle is caused to temporarilystop without passing through the target point.

The autonomous driving system 100 does not necessarily need to recognizethe lighting state of the traffic signal. The autonomous driving system100 may have a configuration in which the vehicle is caused to passthrough the target point or to stop without passing through the targetpoint depending on the driver's trigger input, without recognizing thelighting state of the traffic signal. In this case, the autonomousdriving system 100 does not need to include a traffic signal recognitionunit 18.

The autonomous driving system 100 does not necessarily need to have are-requesting function when it is recognized that the traffic signal isnot in the passing permitted state. The trigger input request unit 16may have a configuration in which only the notification is performed onthe driver that the traffic signal is recognized as not being in thepassing permitted state, without performing the trigger inputre-request. In this case, the vehicle control unit 19 causes the vehicleto pass through the target point along the passing route when the driverdoes not perform the trigger cancellation operation (or an autonomousdriving end operation).

In addition, in the re-request function described above, the autonomousdriving system 100 may perform only the trigger input re-request withoutperforming the notification that the traffic signal is recognized as notbeing in the passing permitted state. In addition, the trigger inputrequest unit 16 may be configured to perform the notification and thetrigger input re-request only when it is recognized that the trafficsignal is in the passing prohibited state, and to perform thenotification and the trigger input re-request when the traffic signal isrecognized as being in the transition state.

The autonomous driving system 100 does not necessarily need to have are-request function when the switching of the traffic signal to thestate other than the passing permitted state is recognized. The triggerinput request unit 16 may be configured to perform only the notificationthat the traffic signal is switched on the driver when the switching ofthe traffic signal to a state other than the passing permitted state isrecognized.

In addition, in the re-request function described above, the triggerinput request unit 16 may perform only the trigger input re-requestwithout performing the notification that the traffic signal is switched.In the re-request function described above, the trigger input requestunit 16 may be configured to perform the notification that the trafficsignal is switched and the trigger input re-request only when theswitching of the traffic signal to the passing prohibited state isrecognized, and not to perform the notification that the traffic signalis switched and the trigger input re-request even when the switching ofthe traffic signal from the passing permitted state to the transitionstate is recognized.

The autonomous driving system 100 does not necessarily need to have asecond request function when the switching of the traffic signal to thestate other than the passing permitted state is recognized. The triggerinput request unit 16 may be configured to perform only the notificationon the driver that the switching of the traffic signal to the passingpermitted state is recognized if the switching of the traffic signal tothe passing permitted state is recognized while the of the driver'strigger input is not detected after the trigger input request. Thetrigger input request unit 16 may be configured not to perform anynotification even if the switching of the traffic signal to the passingpermitted state is recognized.

The autonomous driving system 100 does not necessarily need to performthe determination (S52, S62) whether or not the vehicle can stop intime. In the case where the vehicle is caused to pass through the targetpoint along the passing route, when the driver's trigger cancelation isdetected, the vehicle control unit 19 may cause the vehicle todecelerate and stop even if the deceleration increases. The triggerinput request unit 16 may perform the notification on the driver thatthe switching of the traffic signal to a state other than the passingpermitted state is recognized regardless of whether the stop of thevehicle is in time or not. The autonomous driving system 100 may set theintersection 60 as the target point even when the situation of thedestination of right turn at the intersection 60 can be detected such asa case where the building 80 is not present in FIG. 10A.

The autonomous driving system 100 does not necessarily need to performthe deceleration start notification (S38 and S70). The autonomousdriving system 100 may start the deceleration to cause the vehicle tostop without performing the deceleration start notification.

What is claimed is:
 1. An autonomous driving system configured toperform an autonomous driving of a vehicle, comprising: an electroniccontrol unit (ECU) including a processor programmed to: perform atrigger input request for requesting a driver of the vehicle to performa trigger input for causing the vehicle to pass through a target pointif the autonomously driving vehicle approaches the target point set inadvance and positioned on a traveling route of the vehicle; detect thedriver's trigger input; cause the vehicle to pass through the targetpoint if the trigger input is detected, and cause the vehicle todecelerate and stop without passing through the target point if thetrigger input is not detected; recognize a lighting state of the trafficsignal which is located in the target point and is corresponding to atraveling route of the vehicle; cause the vehicle to pass through thetarget point without performing the deceleration of the vehicle when thetrigger input is detected before starting the deceleration of thevehicle for causing the vehicle to stop without passing through thetarget point in this casein a case in which the traffic signal isrecognized as not being in the passing permitted state; and cause thevehicle to stop the deceleration and to pass through the target pointwithout temporarily stopping when the trigger input is detected afterstarting the deceleration of the vehicle in a case in which the trafficsignal is recognized as not being in the passing permitted state,wherein the ECU is programmed to notify the driver that the trafficsignal is recognized as not being in a passing permitted state andperform a trigger input re-request if the traffic signal is recognizedas not being in the passing permitted state and the trigger input isdetected; and the ECU is programmed to cause the vehicle to pass throughthe target point without temporarily stopping if the trigger input isdetected after the trigger input re-request, and cause the autonomouslydriving vehicle to decelerate and stop without passing through thetarget point if the trigger input is not detected after the triggerinput re-request.
 2. The autonomous driving system according to claim 1,wherein the target point is a pedestrian cross-walk where there is atraffic signal.
 3. The autonomous driving system according to claim 1,wherein the ECU is programmed to notify the driver that the switching ofthe traffic signal to a state other than the passing permitted state isrecognized and to perform the trigger input re-request if the switchingof the traffic signal to the state other than the passing permittedstate is recognized after the trigger input is detected, and wherein theECU is programmed to cause the vehicle to pass through the target pointwithout temporarily stopping if the trigger input is detected after thetrigger input re-request, and to cause the autonomously driving vehicleto decelerate and stop without passing through the target point if thetrigger input is not detected after the trigger input re-request.
 4. Theautonomous driving system according to claim 1, wherein the ECU isprogrammed to detect at least two inputs as the trigger input among aninput by a driver's manual operation to a trigger input unit provided inthe vehicle, an input by a driver's acceleration operation to anaccelerator pedal of the vehicle, and an input by a driver's contact toa touch sensor of the vehicle, and request the driver to perform onetype of the trigger input in the trigger input request, and request thedriver to perform a plurality of types of the trigger input in thetrigger input re-request.
 5. A control method of an autonomous drivingsystem that performs an autonomous driving of a vehicle, the methodcomprising: requesting a driver of the vehicle to perform a triggerinput for causing the vehicle to pass through a target point if theautonomously driving vehicle approaches the target point set in advance;detecting the driver's trigger input; controlling the autonomouslydriving vehicle to pass through the target point if the trigger input isdetected, and to decelerate and stop without passing through the targetpoint if the trigger input is not detected; recognizing a lighting stateof a traffic signal which is located in the target point and iscorresponding to a traveling route of the vehicle; wherein, in the stepof controlling the vehicle, the vehicle is caused to pass through thetarget point without performing the deceleration of the vehicle when thetrigger input is detected before starting the deceleration of thevehicle for causing the vehicle to stop without passing through thetarget point in a case in which the traffic signal is recognized as notbeing in the passing permitted state; and wherein, in the step ofcontrolling the vehicle, the vehicle is caused to stop the decelerationand to pass through the target point without temporarily stopping whenthe trigger input is detected after starting the deceleration of thevehicle in a case in which the traffic signal is recognized as not beingin the passing permitted state, wherein, in the step of controlling thevehicle, notify the driver that the traffic signal is recognized as notbeing in a passing permitted state and perform a trigger inputre-request if the traffic signal is recognized as not being in thepassing permitted state and the trigger input is detected; and cause thevehicle to pass through the target point without temporarily stopping ifthe trigger input is detected after the trigger input re-request, andcause the autonomously driving vehicle to decelerate and stop withoutpassing through the target point if the trigger input is not detectedafter the trigger input re-request.
 6. The control method of theautonomous driving system according to claim 5, wherein the target pointis a pedestrian cross-walk where there is a traffic signal.
 7. Thecontrol method of the autonomous driving system according to claim 5,wherein, in the step of controlling the vehicle, notify the driver thatthe switching of the traffic signal to a state other than the passingpermitted state is recognized and to perform the trigger inputre-request if the switching of the traffic signal to the state otherthan the passing permitted state is recognized after the trigger inputis detected, and cause the vehicle to pass through the target pointwithout temporarily stopping if the trigger input is detected after thetrigger input re-request, and to cause the autonomously driving vehicleto decelerate and stop without passing through the target point if thetrigger input is not detected after the trigger input re-request.
 8. Thecontrol method of the autonomous driving system according to claim 5,wherein, in the step of detecting the trigger input, at least two inputsas the trigger input among an input by a driver's manual operation to atrigger input unit provided in the vehicle, an input by a driver'sacceleration operation to an accelerator pedal of the vehicle, and aninput by a driver's contact to a touch sensor of the vehicle, andrequest the driver to perform one type of the trigger input in thetrigger input request, and request the driver to perform a plurality oftypes of the trigger input in the trigger input re-request.
 9. Anon-transitory computer readable medium having stored thereoninstructions which, when executed by at least one ECU, cause the atleast one ECU to execute processing comprising: requesting a driver ofthe vehicle to perform a trigger input for causing the vehicle to passthrough a target point if the autonomously driving vehicle approachesthe target point set in advance; detecting the driver's trigger input;controlling the autonomously driving vehicle to pass through the targetpoint if the trigger input is detected, and to decelerate and stopwithout passing through the target point if the trigger input is notdetected; recognizing a lighting state of a traffic signal which islocated in the target point and is corresponding to a traveling route ofthe vehicle; wherein, in the step of controlling the vehicle, thevehicle is caused to pass through the target point without performingthe deceleration of the vehicle when the trigger input is detectedbefore starting the deceleration of the vehicle for causing the vehicleto stop without passing through the target point in a case in which thetraffic signal is recognized as not being in the passing permittedstate; and wherein, in the step of controlling the vehicle, the vehicleis caused to stop the deceleration and to pass through the target pointwithout temporarily stopping when the trigger input is detected afterstarting the deceleration of the vehicle in a case in which the trafficsignal is recognized as not being in the passing permitted state,wherein, in the step of controlling the vehicle, notify the driver thatthe traffic signal is recognized as not being in a passing permittedstate and perform a trigger input re-request if the traffic signal isrecognized as not being in the passing permitted state and the triggerinput is detected; and cause the vehicle to pass through the targetpoint without temporarily stopping if the trigger input is detectedafter the trigger input re-request, and cause the autonomously drivingvehicle to decelerate and stop without passing through the target pointif the trigger input is not detected after the trigger input re-request.10. The non-transitory computer readable medium according to claim 9,wherein the target point is a pedestrian cross-walk where there is atraffic signal.
 11. The non-transitory computer readable mediumaccording to claim 9, wherein, in the step of controlling the vehicle,notify the driver that the switching of the traffic signal to a stateother than the passing permitted state is recognized and to perform thetrigger input re-request if the switching of the traffic signal to thestate other than the passing permitted state is recognized after thetrigger input is detected, and cause the vehicle to pass through thetarget point without temporarily stopping if the trigger input isdetected after the trigger input re-request, and to cause theautonomously driving vehicle to decelerate and stop without passingthrough the target point if the trigger input is not detected after thetrigger input re-request.
 12. The non-transitory computer readablemedium according to claim 9, wherein, in the step of detecting thetrigger input, at least two inputs as the trigger input among an inputby a driver's manual operation to a trigger input unit provided in thevehicle, an input by a driver's acceleration operation to an acceleratorpedal of the vehicle, and an input by a driver's contact to a touchsensor of the vehicle, and request the driver to perform one type of thetrigger input in the trigger input request, and request the driver toperform a plurality of types of the trigger input in the trigger inputre-request.